# Interest group forums > Electrical Contracting Industry Forum >  Generator connection

## ians

I am getting lots of generator inquiries again, people are getting nervous and want to prepare themselves for what they think is going to happen.

I have a simple solution and would like to hear your thoughts.

For my own house i am using a 2.2 kva generator.

I have a changeover switch mounted directly above my meter box, fed from the 60 amp circuit breaker using a 16 mm wire into one side of the changeover switch.

I have a 16 amp plug top with a 2.5 mm x 3 core feed from the generator to the other side of the changeover switch ( the generator has built in overload protection)

from the other side of the changeover switch i have run a 16 mm wire which is connected to wire feeding the house in the meter box using a ferrule and heat shrink.

For my application as an electrician i know what to switch on and off as i have a current clamp and have replaced my element in my geyser for example to a 1kw element. 

I would recommend a 5.5 kva generator or bigger to customers, but with this comes a few challenges.

My question to you all fellas...

1/ Would you recommend this setup to your customers, considering they dont have a current clamp?

2/ How do you overcome the problem of supplying 20- 25 amps (5.5 kva generator) via a 16 amp sockets outlet? 

3/ Would you use a circuit breaker next to the generator to protect the cable or rely on the generator overload protection?

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## Justloadit

I think that the generator may not supply the current you think it can. Note that a grid has a low impedance and is able to supply the current demand, as per a generator, which has a high impedance, and would overload the motor any way to the point that it would probably choke and stop. All the generators that I have seen have a circuit breaker.

With respect to the 16A plug, the generator will probably struggle to supply that , with the CEE plugs are under rated anyway, so the few extra amps wont do any heating of the plug. Bear in mind, that the generator would probably never run at full power for long periods of time anyway. Maybe include a moving iron amp meter which is relative inexpensive as a gauge for the customer.

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## AndyD

I would personally never recommend a generator for a domestic customer, by the time you work out the capital outlay, the installation, the fuel cost, the fuel storage, the servicing etc the real cost per kWh is absolutely extortionate and the smaller generators are often completely not suitable for connection to a DB plus unless it's a high-end unit the frequency and the voltage instabilities cause havoc with electronics etc.

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## Justloadit

Hi Andy,

I agree with you on your statement as far as a large generator is concerned however, what we are doing here in  Jhb, is installing a 5.5KVA genny, with a manual change over switch, connected to the DB board, BUT, we isolate a number of circuits only which are connected to the generator. Usually lights, fridge circuit and entertainment circuit. 

Basically during a black out, the user starts the genny via a key switch on the genny, as most 5.5Kva have an electric start, once running, they change the switch manually to genny, have power during the black out, and when the power returns, they simply change over back to mains, switch the genny off and wait for the next one.

This makes it safe for any one to use, and due to the simplicity can even be done by the home manager if required during the day.

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## wynn

When the power goes off I know to switch the 'Genny' on because there is no power, but how do I know the power is back on if my 'Genny' is running?

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## ACEsterhuizen

You can wire the change over switch with a pilot light and a pulse once (or more) alarm or a manual alarm cancel switch so you will know when eskom power is back on, or, as described above, if you only wire certain circuits through the change over switch, the other circuit will obviously become "live" once eskom is back on, eg you leave the some light on which is NOT wired to the Gennie and that light will remain off as long as eskom is off and will come on once eskom is on.

Just remember to have the install done by a registered electrician (ask for proof and follow up and get a coc for the job) The Neutral Bar must be split according to the regs i have seen many installs where the neutral bar was not split. (except if it a 3 phase install at the mains)

_7.12.3.1.4 Where only part of an installation is switched to the alternative
supply in the same distribution board, the neutral bar shall be split (see
figures S.2 and S.3 in annex S)._

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## AndyD

The problem with a lot of the small generators is the the neutral is at an equal voltage as the live with respect to earth so they're configured 115(L)-0(Earth)-115(Neutral) L-N is 230v. You cannot connect this type of genny to a DB, it's designed for use with trailing leads only. Also genny's are notoriously poor at producing sufficient current in the case of a fault and don't achieve required disconnection times of circuit breakers or other OCPD's.

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## Houses4Rent

I am thinking of a far simpler set up. I really only need power during load shedding and other outages for my PC, printer, router, screen etc. so I can continue working. Is it feasible if I buy a small genny (what size would I need?) and when the power went I just start up the genny and use an extension to plug my PC gear straight into the genny. 

What are the pros and cons/risks?

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## wynn

On 'The Other' Forum it was discussed that you would set up a series of batteries (Deep Cell) in a cage outside your office (say under the roof eaves) and run an inverter through them to your necessary equipment (PC, screen, printer, router, remote phone and emergency lights) so they would all work during a 'Load Shit' and as soon as power came back on it would recharge the batteries for the next 'Dump', like a giant UPS.

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## Dave A

> 2/ How do you overcome the problem of supplying 20- 25 amps (5.5 kva generator) via a 16 amp sockets outlet?


Typically those generators have two socket outlets. If you expect to push past 15A, perhaps use both outlets in parallel?




> I think that the generator may not supply the current you think it can. Note that a grid has a low impedance and is able to supply the current demand, as per a generator, which has a high impedance, and would overload the motor any way to the point that it would probably choke and stop. All the generators that I have seen have a circuit breaker.


Definitely go with voltage regulated generators. This solves lots of problems.




> The problem with a lot of the small generators is the neutral is at an equal voltage as the live with respect to earth so they're configured 115(L)-0(Earth)-115(Neutral) L-N is 230v.


Is the earth tapped in the middle like that, or is it just that without an anchor the live and neutral float off the "ambient" earth voltage in equal measure? 

My experience so far is if you bridge the earth and neutral at the generator, the neutral stays at 0V and live goes to 220V relative to earth, which solves the problem. Of course, make sure your earthing system is appropriate (have an earth spike).

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## IanF

> I am thinking of a far simpler set up. I really only need power during load shedding and other outages for my PC, printer, router, screen etc. so I can continue working. Is it feasible if I buy a small genny (what size would I need?) and when the power went I just start up the genny and use an extension to plug my PC gear straight into the genny. 
> 
> What are the pros and cons/risks?


That's what I do. Then when the power comes back the lights come on.

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## KCS

We have kept it simple, as we don't need to power the whole house during the outages. My big concern was charging my laptop, phones, security and the fridge. The rest we can do without, and we use battery LED lights. Also have gas for cooking (braai!) 

In view of this I bought a 3,5 kva generator which I installed with a nice thick lead to a multiplug, located near the fridge. During outages I just plug in the fridge, and switch off the fridge when we need to boil the kettle or charge any of the devices. The generator has a decent earth into the ground, as well as AVR (I assume this means Automatic Voltage Regulator?) as well as an overload cut-off. 

This kept it really simple and the cost very low. Also, I never plug the computer straight into the generator power supply, only use it to charge, so I assume that the charger will take the brunt should there be a spike in current? 

The question marks above are assumptions, I am not an electrician. Would welcome comments. 

Cheers

KC

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## ians

> The problem with a lot of the small generators is the the neutral is at an equal voltage as the live with respect to earth so they're configured 115(L)-0(Earth)-115(Neutral) L-N is 230v. You cannot connect this type of genny to a DB, it's designed for use with trailing leads only. Also genny's are notoriously poor at producing sufficient current in the case of a fault and don't achieve required disconnection times of circuit breakers or other OCPD's.


Andy why did you have to go spoil it and bring that up. That is why you have to plug it in so that it doesnt become part of the electrical installation. We discussed this issue during the last load shedding episode. Just imagine trying to stop all these generators being connected, there are thousands of them connected to DB's. The worst i have seen to date are the suicide cords, with the plug on both ends of the cable.

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## AndyD

Eek, 'plugging it in' would not be a wise move.




> Is the earth tapped in the middle like that, or is it just that without an anchor the live and neutral float off the "ambient" earth voltage in equal measure? 
> 
> My experience so far is if you bridge the earth and neutral at the generator, the neutral stays at 0V and live goes to 220V relative to earth, which solves the problem. Of course, make sure your earthing system is appropriate (have an earth spike).


In some smaller site type generators the centre of the windings is actually tapped and bonded to the chassis as an earth which ties both L and N at 110v wrt earth, they're not floating. The problem is when the centre tapped earth is bonded internally to the generator chassis. If you bridge a centre tapped earth and neutral you're effectively shorting out half of the winding which would cause a fault condition and probably damage to the windings. This is what would happen with a cowboy connection into a DB. 

These generators are designed to be used with extension leads only.

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## Houses4Rent

Hm, can you sparky's please tell me and KCS how to set up a very simple thing like a generator powering a few things of choice via an extension lead?

I won't need a fridge/freezer as it can survive 2.5h load shedding. I really only need to power my PC (desktop), router, printer and scanner without risking frying any of them due to problems induced by the generator (Voltage & Amp variations). I can charge my cell via USB from the PC

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## AndyD

> Hm, can you sparky's please tell me and KCS how to set up a very simple thing like a generator powering a few things of choice via an extension lead?
> 
> I won't need a fridge/freezer as it can survive 2.5h load shedding. I really only need to power my PC (desktop), router, printer and scanner without risking frying any of them due to problems induced by the generator (Voltage & Amp variations). I can charge my cell via USB from the PC


Just use extension leads to your PC'sand laptops etc. The stability of the voltage and frequency of the generator power is down to how good the built-in AVR is so for electronics it's always worth spending a bit extra and getting a decent genny.

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## Houses4Rent

Thanks Andy, but how does one establish what is a decent genny and AVR? Any trusted brands/sources which can be named (Cape Town).

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## AndyD

I've got limited generator experience but I've always paid the extra and purchased Honda. So far I've not regretted it, some of my gennys have not had an easy life and are over 10 years old.

As with anything I'm sure there's some Chinese brands that are very respectable but the problem is there's a lot that aren't and most of the time you're relying on info from the salesman who's going to tell you anything. The number of times I've heard 'they're made in the same factory as **_insert well known brand name_**' is laughable and not just for generators.

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## ians

Something to note, not all small generators cannot be connected to a house. I indicated to a customer today that it was not wise to connect a small generator to a house. He set the record straight with documentation and a diagram showing how to do it.

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## ians

Diagrams sent to me today, indicating how to connect these generators as standby units.

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## ians

Still a bit concerned about how you can connect a 7.5 kva generator using a 15 amp socket outlet.

I wonder if these generators are SABS approved or have documentation to backup.

Load shedding just started again yesterday, my phone is ringing off the hook for generators installations.

I dont see how an electrician who connects a changeover switch and does an installation with a a plug top, can be held responsible for what the customer plugs into the plug top. So long as he fits a circuit breaker to protect the cables etc. That's like telling me it is my responsibility to make sure every appliance in a house must be checked by me before they use it.

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## Justloadit

You can use one of these 32A CEE sockets

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## AndyD

> ..........I dont see how an electrician who connects a changeover switch and does an installation with a a plug top, can be held responsible for what the customer plugs into the plug top. So long as he fits a circuit breaker to protect the cables etc. That's like telling me it is my responsibility to make sure every appliance in a house must be checked by me before they use it.


 Hmmm, I beg to differ, household appliances don't kill Eskom workers and cable jointers if they're connected up incorrectly........

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aecelectrical (05-Feb-20)

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## Houses4Rent

http://www.moneyweb.co.za/moneyweb-s...tor-generation

Interesting info. Is it sound and correct though?

So to just run a PC a 750W genny is ok?

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## Houses4Rent

Some more useful here info it seems

http://ipowersa.co.za/i_power_usage_calculator.htm

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## AndyD

If it's a normal office PC with an LCD/LED monitor a 750w genny should run it, not sure about office printer etc though, a decent laser prnter would probably take it over the 750w. If it's a gaming PC with a high-end graphics setup the jury is still out, it may or may not depending on the exact setup.

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## ians

> Hmmm, I beg to differ, household appliances don't kill Eskom workers and cable jointers if they're connected up incorrectly........



Maybe my wording wasn't correct. 

If the electrical changeover installation is all done correctly by a qualified electrician, i don't see how it can kill anyone. However if the owner decides to connect a generator he purchased at his local DIY store and was told it was compliant with drawings to show it is possible, then i don't see how the electrician who did the changeover system can be held responsible. 

What if the owner replaces the generator which is plugged into the changeover system. 

My point is if i do the electrical changeover to standard, I cant be help responsible for what the owner plugs into it.

The next question would be, is it legal to fit a socket on the end of a cable designed to connect to a changeover system. IF not, we have an even bigger problem than just the 115 - 115 volt generator being connected. I see hundreds of this type of installation.

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mikilianis (16-Feb-15)

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## DieterT



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Justloadit (31-Jan-15)

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## Justloadit

I have something similar to the pics, except that my in coming plug is close to the switch over board. So I have a long extension from the genny.

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## ACEsterhuizen

Same issue, 15kva Honda, cannot add or change to the gennie wiring otherwise guarantee is gone.  :Banghead:

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## ACEsterhuizen

> The problem with a lot of the small generators is the the neutral is at an equal voltage as the live with respect to earth so they're configured 115(L)-0(Earth)-115(Neutral) L-N is 230v. You cannot connect this type of genny to a DB, it's designed for use with trailing leads only. Also genny's are notoriously poor at producing sufficient current in the case of a fault and don't achieve required disconnection times of circuit breakers or other OCPD's.




Hi Andy will this honda 15kva sp gennie be one of those? (my generator internal workings is limited  :Confused: )

anyway i cannot see this setup with that (2.5mm?) red and black to that plug sustaining a 50-60 Amp load for long but who am i to say that is after all a honda generator with a sabs mark?

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## DieterT

> Eek, 'plugging it in' would not be a wise move.
> 
> 
> In some smaller site type generators the centre of the windings is actually tapped and bonded to the chassis as an earth which ties both L and N at 110v wrt earth, they're not floating. The problem is when the centre tapped earth is bonded internally to the generator chassis. If you bridge a centre tapped earth and neutral you're effectively shorting out half of the winding which would cause a fault condition and probably damage to the windings. This is what would happen with a cowboy connection into a DB. 
> 
> These generators are designed to be used with extension leads only.


Good day AndyD

Thank you for your input in regards to this matter. You have openend my eyes to something I was not aware of.

With some of our installations I noticed a equal voltage on live and neutral.

A long time ago we had a situation where a company installed a 40kVA genset at our client before we became their electrical contractors.

During the time loadshedding just started we where called due to problems that their electronics was blowing and loosing alot of their stage lights globes.

After verious tests we found that there was equal voltage on live and neutral when the genset was active as supply.

Upon further investigation it was found that the genset wasn't earthed properly.

This genset was mounted on a slab with steel fencing around it which also inter-joined with the fencing and cabinets of Telkom / MTN and Vodacom.

Upon further visual inspection it was noted that the neutral where it entered the CB on the genset was bridged with the canopy and to our shock we noticed that when the generator was active the whole canopy, fence and telecoms cabinets where live.

We rectified this by driving a earth rod into the ground and seperating the neutral earth bridge from the structural earth.

This also fixed the issue with the voltage, now being 230v on live and 0v on neutral.

Now with recent installations with these portable generators same problem with the equal voltage over live and neutral was found and I do understand from what you explained about the way the center tap has been connected that, that is excatly the case.

I was considering to then tell the client he needs to mount the genset to the ground and then bridge out neutral with the earth spike under the genset using a protected earth (just like a transformer on the star point) and then also earth the genset structure to the same earth spike.

But as you explained making the short over the winding could damage the winding?

Could you please explain to me how this will be different in the mounted gensets like the one where we fixed the neutral earth bridge towards the portable gensets?

And also how using a extension lead solves this problem?

One thing I also noticed is that when the portable genset is supplying power to the DB it has 115v over live and 115v over neutral, but as soon as I switch on the mains it goes to 230v live and 0v neutral. The change over switch seperates the supplier live/neutral from the load so it can't be the earth/neutral bridge from supplier.

Thank for your time in this matter

"I used to have a lot of anger issues, now I just have a passion for justice"

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## Sparks

Does anyone know Schultz generators? Are they reliable?

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## DieterT

Just out of interest sake and because of all the electrical contracting business I know nobody knows about this (until 2weeks ago I also did not know half of this)

When installing a generator as alternative supply a generator application form needs to be completed and submitted to supplier including generator, make, model and serial number including a CoC with relevant test certificate.

As for installation part, a earth neutral bridge is required where generator is connected and properly labeled as such.

Always ask when buying a generator if this generator can be issued as an alternative supply (in other words be connected to mains with switch over)

A switch over cutting out live/s + neutral must be installed (Supplier / Off / Generator)

If its a manual change over then all DB boards fed from this supply must have labeling indicating that a generator backup supply is feeding this board

If its an automatic change ovet system then all DB boards feeding from this supply must have indicating lights showing when generator supply is active.

I will try and upload the relevant documentation when I get a chance.

"I used to have a lot of anger issues, now I just have a passion for justice"

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## Dave A

> When installing a generator as alternative supply a generator application form needs to be completed and submitted to supplier including generator, make, model and serial number including a CoC with relevant test certificate.


This probably varies dependant on the supply authority concerned.

I like the idea of attaching the various requirements to this thread though. Here is the one from Ethekwini.

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## Sparks

Hmmm, "Temp supply", "Back-up" supply, "Alternative supply", "Emergency supply"

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## Rohann van Zyl

Ok guys...this is my first time, i have it like this.  I get loads of customers also asking questions about these generator and ups/ invertors... My argumemt is that if i say no i cant do it they will go to someone that will help them and that person will 10 to 1 know less than some of us....so i think that we realy dont have   controle as to whatever a client is going to use as a source.  So my opinion is that we supply a manual (20A) switchover switch with a small db with 1plug circuit and light circuit with mains sp&n and on the other end... like a male 16A welding plug.....wich have a small "shroud db" with a earth leakage in.  Now the client can make a lead to plug in either a generator or invertor... here we dont have controle..we can put mains power on this plug and do c.o.c. 
I also tell them that a vov generator is not suppost to be pluged in to this instalation because of regulasion.  I use mine like this and in my eys its save enought.  I know the earth leakage is working if you press the test button and not with the plug in tester that creats a earth fault....and im not so sure why...maybe someone clever can help us out....but the earth of the supply authority/ earth spike etc. Is connected right thrue the system so i feel quite save.  If someone have good advise to ad...please ...if i'm wrong ! Help me so we all can do the right thing outthere! Thanks for reading

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## Justloadit

Simply remember that Inverters are usually isolated from the source of energy, most likely batteries, and so the output supply is floating. There is no "Neutral" or "Live"  on an inverter. When connecting the inverter to a system, which has an ELB, then you have to decide, which wire from the inverter, you are going to make a "Neutral" with. This is simple, either connect the one wire from the inverter to the system Earth directly, or use a 100ohm 100Watt resistor to earth. This line is now called "Neutral", the other line is now "Live"

I recommend that one output wire from the inverter is earthed, simply because it adds more safety to the system. If you understand surges and mains spikes, you will realise that if you leave the lines from the inverter floating, that tremendously high voltages can develop between the energy source,the load across the internal transformer of the inverter and any other load connected to the system DB which is connected via the earth of the DB, which is very dangerous and life threatening. I have seen voltages in the thousands of volts when there is a lightning strike close by. Earthing and connecting the inverter "Neutral" to earth, ensures that the DB grid remains at a safe potential.

Off course before earthing the Inverter ensure that the model inverter you have is not already internally earthed. This can be done with an ohm meter, simply measure the resistance from the inverter earth to either of the supply wires to see if there is a reading. No reading means there is no earth connection.

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## Justloadit

Another point, if solar panels are being used to charge the batteries for an inverter, ensure that the solar panel is earthed, and I recommend that "Negative" side of the solar panel wire that is connected to the first battery be joined to earth as well. The generation of static electricity during high winds and storms is unbelievable, until you see the arcing on the wires to earth.

Radio hams will testify to this phenomena, especially when you have a wire or a metallic object isolated from earth and in the path of the wind. The effect is very similar to a Van der Graf generator.

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## Sparks

> Ok guys...this is my first time, i have it like this.  I get loads of customers also asking questions about these generator and ups/ invertors... My argumemt is that if i say no i cant do it they will go to someone that will help them and that person will 10 to 1 know less than some of us....so i think that we realy dont have   controle as to whatever a client is going to use as a source.  So my opinion is that we supply a manual (20A) switchover switch with a small db with 1plug circuit and light circuit with mains sp&n and on the other end... like a male 16A welding plug.....wich have a small "shroud db" with a earth leakage in.  Now the client can make a lead to plug in either a generator or invertor... here we dont have controle..we can put mains power on this plug and do c.o.c. 
> I also tell them that a vov generator is not suppost to be pluged in to this instalation because of regulasion.  I use mine like this and in my eys its save enought.  I know the earth leakage is working if you press the test button and not with the plug in tester that creats a earth fault....and im not so sure why...maybe someone clever can help us out....but the earth of the supply authority/ earth spike etc. Is connected right thrue the system so i feel quite save.  If someone have good advise to ad...please ...if i'm wrong ! Help me so we all can do the right thing outthere! Thanks for reading



Please tell me that your customers are not making use of you as an electrician and that you are not working on electrical installations! :No:

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## Rohann van Zyl

> Please tell me that your customers are not making use of you as an electrician and that you are not working on electrical installations!


I did not think i`ll get this response - Sparks, you sound like someone allmighty and mr know it all - without reason or explanation, throw that curve ball, nice going. Congrats! but we all are not.  So why not help me right? or dont you know either?

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## Sparks

The reasons for my valid response:
"I get loads of customers also asking questions about these generator and ups/ invertors..."
"we supply a manual (20A) switchover switch" 
"I know the earth leakage is working if you press the test button and not with the plug in tester that creats a earth fault....and im not so sure why"

It appears your clients believe you to be a "competent electrician" I do not.
20A Change-over switch being fed from a 60-100A municipal supply?
You do not know why the ELCB tester does not trip the ELCB yet still issue a COC?

Besides your obvious lack of knowledge regarding SANS10142(The regulations!), your spelling and grammar lead me to wonder whether you are not in fact a government official!

Please humour us with your definition of a "competent electrician"

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## bergie

if your supply from mains db to the changeover switch is fed from a 20 amp circuit breaker then you can use a 20 amp changeover as no more than 20 amps can flow through there.

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## Rohann van Zyl

> The reasons for my valid response:
> "I get loads of customers also asking questions about these generator and ups/ invertors..."
> "we supply a manual (20A) switchover switch" 
> "I know the earth leakage is working if you press the test button and not with the plug in tester that creats a earth fault....and im not so sure why"
> 
> It appears your clients believe you to be a "competent electrician" I do not.
> 20A Change-over switch being fed from a 60-100A municipal supply?
> You do not know why the ELCB tester does not trip the ELCB yet still issue a COC?
> 
> ...


The 20Amp switch over switch (feeding a small DB with 1 light and 1 plug circuit) - that is getting fed from either 20A CB in Db and/ or 20A CB with earth leakage that comes from the "ecc type male" plug (where for testing purposes been tested with mains power).  So DON`T BE CHILDISH - its like in SANS10142-1 last page (358) . MR no it all sparks.  


So is there any other commends on this or not?  Thank you

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## DieterT

So this welding socket 3pin, was it rated 16A you said?...

"I used to have a lot of anger issues, now I just have a passion for justice"

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## ACEsterhuizen

Its Friday....

True Story...

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## Sparks

Yes it is, all day. Let's clear the air. Rohann van Zyl is actually Afrikaans, that explains some of his post. The rest of my comment still stands however. If a person does not know the reason the ELCB tester does not trip the ELCB then I have no choice other than to doubt their credentials. In light of this there is no way that I will assume that the "mains supply" which he refers to is from a 20A circuit breaker, especially when specific reference is made to "mains supply". Rohann as well as any other Afrikaans speaking people are welcome to search for "eresme" on Skype if they wish to converse in Afrikaans which will certainly eliminate misunderstandings caused by translation.

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## DieterT

So all in all I feel this discussion of DYI should be made into a new thread as it is a very important aspect to discuss and to be clear about. If only our country could have created a DYI regulation as what NZ has done and to say where the client needs to get a registered person. Anyways back to generators.

"I used to have a lot of anger issues, now I just have a passion for justice"

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## DieterT

Are we all in agreance of the fact that a generator connection requires a switch over that breaks phases and neutral with indication on db boards supplied by generator.

Also that a neutral earth bridge is required at generator point of connection and properly labeled as such.

Further more a circuit breaker on generator supply in order to protect against short circuit and overload conditions.

Also a valid CoC for the installation of alternative supply.

A application form seems to be only required by certain manucipalities, maybe some of you could elabirate more on that.

Further more with plug in generators for us the registered electricians. This is not some law in the OHSA nor in the SANS10142-1

This is something I believe in and from many conversations with other professionals "ECSA registered engineers" and the electrical inspector for Gauteng I feel and it should be required of us professionals to best possible advise the client and also not to leave the client in a position that he can cause possible harm or damage to property or harm to himself or other persons.

This having been said due to the plug in generator, since the generator plugged in is CoC'd as its feeding the load as alternative supply thus the load must be compliant with the supply and vice versa (PSCC, loop impedance etc.)

Now the client buys a new generator or that generator is serviced, maybe rewound some changes come due to this then this is used again as alternative supply since the plug in point is provided.

It could cause problems which the client is not aware of or who ever comes after him. This then is the responsibility of the professional to make sure that this could not happen.

There for in my opinion and take it only as that, that a connection must be installed where the generator is physically connected to with the earth/neutral bridge inside, thus when generator is removed or replaced an electrician needs to come and do so then also with new generator or rewound/repaired generator do new CoC.

Thus having to use a tool to remove and connect generator is then within regulations as a layman is not allowed to do so just as with any other connection, but with plug in point that changes completely...

Any sound advise or comments on this is welcomed and please don't come with bullshit like "then its the client's own responsibility" and " the regulations protect me from responsibility"

At the end of the day I don't want any one's death on my hands, nor law suits at my back. I believe it is my responsibility as an professional even thou the regulation can so be munipulated to edemnify me from responsibilty, that I must ensure the safety of human beings, animals and protection of property against fire and short circuit damage.

Excuse my spelling mistakes as I am laying in hospital awaiting a back opp and not using google spelling mistake correction.

I look forward to other opinions on this and also for everyone to offer clarity on generator connections and installations.

"I used to have a lot of anger issues, now I just have a passion for justice"

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## Sparks

I agree Dieter, unfortunately there are way too many "electrical assistants/appys'" running around making hot connections along with DIYers. Many sparkies put their client's safety above the buck but unfortunately once again the clients are more concerned about saving the buck. I refuse to sign off any COC unless I am satisfied that the installation is either compliant or safe as applicable. All the best with your back op.

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## DieterT

Thnx Sparks. Yes and that is the attitude all sparkies should carry around. Don't sign the certificate if it does not comply. But unfortunetly there are a lot of desperate sparkies out there who would turn the blind eye for some extra cash in his pocket.

"I used to have a lot of anger issues, now I just have a passion for justice"

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## SilverNodashi

> Thnx Sparks. Yes and that is the attitude all sparkies should carry around. Don't sign the certificate if it does not comply. But unfortunetly there are a lot of desperate sparkies out there who would turn the blind eye for some extra cash in his pocket.
> 
> "I used to have a lot of anger issues, now I just have a passion for justice"


And quite often they're more expensive as well!

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## Matt_k

Hi Guys,

Most of you seem rather knowledgeable, so I'd like to garner your opinion regarding grounding of a portable generator.

I recently purchased a Kipor IG2600 (2.6Kva) Digital Inverter gennie as I want to power things like our entertainment system, or my desktop PC etc. Now I have tested it and it all works swimmingly well. The Digetal Inverter type generators cost quite a bit more than your builders 'special' generators, and have AVR, Overload etc. I would like to believe that they quality of the components is of a good quality since I paid a bit of a premium. Other than the quality aspect, main reason that I bought it is because I stay in a complex and noise is an issue so wanted the quietest (within budget) generator available as so not to disturb my neighbours.

Now my main question I have for you brainiac's is what options do I have regarding grounding of my generator? I have read about ground spikes etc, but info is a bit slim online in SA, and parts for that matter as well. Also since I have a new house in a complex, building rubble is abundant in my garden, so driving a 2.4m copper rod into the ground might prove somewhat challenging...

Is it possible to ground it to the water pipes perhaps? I know I have a garden tap outside which appears to have a metal pipe running up the wall out of the ground, so was considering this (if the pipe is copper). If possible, I would prefer to try and do the installation myself within reason, as I have gotten some quotes from some electricians in my area for a Manual Transfer switch installed, and the amounts where laughable... One wanted to charge me R7995 for just a switch mounted with a plug right at my DB board in the garage which I'm pretty sure is daylight robbery.

I know it won't power the house and as mentioned before it doesn't need to, just would be easier to isolate the circuits I want (LED lights and lounge plugs) for the DB switch. But for now I'd settle just to sort out the Grounding so I know it is safer. I am not an electrician, i'm just a normal guy that likes to do his own DIY.

Just a FYI with the generators, in my manual it was quite handy at showing the power loss for the generators at altitude. It stated for every 305 meters above sea level, your gen will lose 3% ( if I remember correctly, will check tonight). Plus then you lose some more for temperature as well, so make sure when buying a Gen, that you have about 20 - 30% in reserve of what you actually need on the highveld because of those losses to be safe.

Thanks again,

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## AndyD

I'd suggest you refer back to the suppliers because I suspect this generator is not suitable for connection to a DB. Page 13 of the manual '*Do not connect the generator to a household circuit. This could cause the damage to the generator or to electrical appliances in the house.*'

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## Matt_k

The manual does mention that it can be connected to the house via a Manual Transfer Switch, but that aside, do you have any thoughts about the grounding of said generator? out of interest, with new complexes these days, what seems to be the norm when it comes to grounding? (in general from your experience)

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## AndyD

> The manual does mention that it can be connected to the house via a Manual Transfer Switch, but that aside, do you have any thoughts about the grounding of said generator? out of interest, with new complexes these days, what seems to be the norm when it comes to grounding? (in general from your experience)


The problem is that with your Eskom supply the neutral and the earth are connected at source. With the AVR output from the generator there is no neutral as such, both output wires are effectively lives and neither are connected in any way the the 'ground' terminal on the generator body or frame. 

What this means is that if you connect it to your DB via a transfer switch the neutrals of the circuits in your house effectively become live. Just some of the problems this raises are that overload protection devices (circuit breakers) in you DB only protect the live of the circuits, with the generator supplying the installation it's possible to get overload faults on the neutral which won't trip. Also the sockets in your house will only have a switch that disconnects the live of the supply circuit, again this means that the 'neutral' which is now actually another 'live' is not disconnected. Same with applianxces, most on/off switches only control the live not the neutral. 

TS Bulletin 2013-006.pdf

Even the service agents seem to get confused about generator output configurations.

The list of problems goes on but the bottom line remains the generator isn't safe to use as a permanently installed back-up supply. If you do connect it to your DB and someone gets injured or killed you'll be the responsible person. Use it as it was intended with extension leads and with the ground terminal on the frame of the generator connected to an earth rod.

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## Matt_k

Thanks AndyD, yeah I will just use the extension cord then. I have a 25A outdoor cable so it is properly rated for anything that the generator can throw at it.

Regarding the grounding, where can I find a ground rod, or is it possible to ground it to the water pipe or something? As mentioned, since my garden has quite a bit of building rubble in the soil the ground rod of 2.4m might be a slight problem.

Thanks,

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## AndyD

You can buy earth rods at any electrical wholesaler but if you use these you'll need to test how effective that earth is after you've knocked them in which is a bit tricky without the proper test equipment. The water pipe bonding isn't ideal, again you'd need to test it first. 

I'd suggest connecting to the main earth terminal of the house if it's accessible. If the house was recently built there might be an earth terminal above the ceiling or somewhere around the DB which is specially provided for other services.

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## Paul Sabatier

There is a previous topic http://www.theforumsa.co.za/forums/s...rth-connection

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## JacquesPN

> Hi Andy,
> 
> I agree with you on your statement as far as a large generator is concerned however, what we are doing here in  Jhb, is installing a 5.5KVA genny, with a manual change over switch, connected to the DB board, BUT, we isolate a number of circuits only which are connected to the generator. Usually lights, fridge circuit and entertainment circuit. 
> 
> Basically during a black out, the user starts the genny via a key switch on the genny, as most 5.5Kva have an electric start, once running, they change the switch manually to genny, have power during the black out, and when the power returns, they simply change over back to mains, switch the genny off and wait for the next one.
> 
> This makes it safe for any one to use, and due to the simplicity can even be done by the home manager if required during the day.


What you are doing is actually in almost every case illegal and very dangerous.
Most generators under 12Kva are PNP devices meaning that if you measure between the L-E you will get 115VAC, N-E 115VAC and L-N 230VAC.

SANS is very clear that these devices may not be connected to the DB.

SANS calls for the earth and neutral to be bonded, and clearly you can not do this on a PNP device as you would make the earth live.
All Honda, Briggs, Yamaha and their cheap Chinese duplicates are PNP devices and as such may NOT be connected to your DB. The only legal way to use them is via a lead which the end device is connected to. There one exception is a HONDA EU imported from Europe which is a true NPN generator, for some unknown reason Honda SA does not bring this into SA.

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## Dave A

:Hmmm:  And if there is no center tap to earth?

I can't help wonder if many of the gensets out there are not actually V-O-V with a center tap to earth, but actually "safe supply" arrangements.

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## JacquesPN

> And if there is no center tap to earth?
> 
> I can't help wonder if many of the gensets out there are not actually V-O-V with a center tap to earth, but actually "safe supply" arrangements.


As I said (save for a few special builds) almost every generator under 7KVA is V-O-V (PNP). they are not designed for use as standby sets but rather as temporary supply via a lead. As long as your not connecting to the DB or feeding into the building supply in any other way these are legal, but the second you feed into the building they become illegal because there is no way you can bond the Neutral to the earth. 

What amasses me is that there are so many of these illegal installations, and they are being done by registered electricians and neither the ECA or the ECB have made any effort to stop this or to advice the public of the dangers.

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## Dave A

With respect, that doesn't answer the question. 

My 5.5 kVA generator doesn't have a center tap to earth.
In fact there is no connection between the earth point of the generator and the single phase supply it provides. (Insulation test between earth and phase exceeds 1 Mega Ohm).
Am I prohibited from connecting this generator to an electrical installation as an alternate supply?

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## Leecatt

I have been asked to connect up a generator which I have not seen yet and this was going to take place this morning.
 I have never connected a generator before because of the absolute minefield it has become, not to mention the confusion. However, I have taken an interest recently due to today's job and I am just wondering, are the regulations the same in version three of 101421 as they were in version 2, regarding the generator? I have yet to purchase version 3. 
Also,I noticed on the SABS website that there is a separate PDF available which deals entirely with the installation of generators. Has anybody purchased this separate PDF and and does it give clear concise instructions?

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## Derlyn

Check your local municipality by laws as well.

Here in our valley we need to apply and get permission from the Munic to do a generator installation.
Technical specs of generator, circuitry and drawings of same are needed to accompany the application.

Attached is a copy of our by laws, but I suggest you check those in your area before doing the job.

https://www.buffalocity.gov.za/folder.php?id=sSWeUsCZg


Peace out   ...   Derek.

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## GCE

> I have been asked to connect up a generator which I have not seen yet and this was going to take place this morning.
>  I have never connected a generator before because of the absolute minefield it has become, not to mention the confusion. However, I have taken an interest recently due to today's job and I am just wondering, are the regulations the same in version three of 10142—1 as they were in version 2, regarding the generator? I have yet to purchase version 3. 
> Also,I noticed on the SABS website that there is a separate PDF available which deals entirely with the installation of generators. Has anybody purchased this separate PDF and and does it give clear concise instructions?


Besides a note added under 7.12.3.1.3 it is basically identical 
I have not seen the generator installation standard 


_7.12.3.1.3 Where alternative supplies are installed remotely from the
installation, or from one another, and where it is not possible to make use of
a single neutral bar or neutral conductor which is earthed, the neutral of each
unit shall be earthed at the unit and these points shall be bonded to the
consumer's earth terminal (see 6.12.4). The supply from each unit which
supplies the installation or part of the installation, shall be switched by means
of a switch that breaks all live conductors operating substantially together (see
figures P.2 and P.4), to disconnect the earthed neutral point from the
installation neutral when the alternative supply is not connected (see also
6.1.6).
NOTE Where four pole switching is implemented, consideration should be given to use
overlapping neutral switching devices._

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## Derlyn

Tested a generator this morning. The specific model   ......   Ryobi rg 6900K.

Results as follows:

No load   .....   L - N   235V ;         L - E  160V ;       E-N   75V

With load ....   L - N   235V ;         L - E  235V ;       E-N    0V

Is there anyone who can explain this.  I'm wracking what's left of my brain cells but cannot understand it.

Peace out  ..  Derek

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## rh1

> Check your local municipality by laws as well.
> 
> Here in our valley we need to apply and get permission from the Munic to do a generator installation.
> Technical specs of generator, circuitry and drawings of same are needed to accompany the application.
> 
> Attached is a copy of our by laws, but I suggest you check those in your area before doing the job.
> 
> https://www.buffalocity.gov.za/folder.php?id=sSWeUsCZg
> 
> ...


I am in Cape Town but a direct customer of Eskom, would COCT by-laws still apply to me?

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## Dylboy

> Tested a generator this morning. The specific model   ......   Ryobi rg 6900K.
> 
> Results as follows:
> 
> No load   .....   L - N   235V ;         L - E  160V ;       E-N   75V
> 
> With load ....   L - N   235V ;         L - E  235V ;       E-N    0V
> 
> Is there anyone who can explain this.  I'm wracking what's left of my brain cells but cannot understand it.
> ...


Best guess is the voltage regulator stuff and perhaps a form of induced EMF on the N and E etc. A generator needs to run on load as far as I understand to run correctly.

I have been told if a generator is producing more than the load it does not like it as it has to keep revs up and not stall but then too much voltage applied etc.

Anyway that's my best so far as to why seeing voltages like that. Also then when it's under load then the genny i believe is then not VoV which is great 

Sent from my SM-N960F using Tapatalk

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## Derlyn

@Dylboy. Yes, not vov for sure. I've checked if vov then the voltage is split 50/50 whether there is a load or not.

Also, I cannot see 3 thick leads coming from the stator. Only 2, live and neutral. On vov wound, there are 3 thick leads coming from the stator with one of them (centre tap ) connected to earth.

Gonna do more tests on Monday.

Gonna connect it to installation and see if earth leakage works as it should.

Peace out  ..  Derek

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## Dylboy

> @Dylboy. Yes, not vov for sure. I've checked if vov then the voltage is split 50/50 whether there is a load or not.
> 
> Also, I cannot see 3 thick leads coming from the stator. Only 2, live and neutral. On vov wound, there are 3 thick leads coming from the stator with one of them (centre tap ) connected to earth.
> 
> Gonna do more tests on Monday.
> 
> Gonna connect it to installation and see if earth leakage works as it should.
> 
> Peace out  ..  Derek


Ah brilliant!  :Smile:  well hope will all be alright once installed! Keep us posted if you can please on the outcome.  :Smile:  

Will try find out more why you got those reading on no load as well  :Smile: 

Sent from my SM-N960F using Tapatalk

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## GCE

> Tested a generator this morning. The specific model   ......   Ryobi rg 6900K.
> 
> Results as follows:
> 
> No load   .....   L - N   235V ;         L - E  160V ;       E-N   75V
> 
> With load ....   L - N   235V ;         L - E  235V ;       E-N    0V
> 
> Is there anyone who can explain this.  I'm wracking what's left of my brain cells but cannot understand it.
> ...


A multi meter has a High Impedance and will tend to pick up " stray " voltages - If you used a meter with low impedance ( duspol tester) you would find the reading would give the same as on load readings

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## Derlyn

Thank you GCE.

I'm going to dig out my Manox from appy days and check it again on Monday.

Enjoy the rest of the weekend.

Peace out  ..  Derek.

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## Leecatt

> Thank you GCE.
> 
> I'm going to dig out my Manox from appy days and check it again on Monday.
> 
> Enjoy the rest of the weekend.
> 
> Peace out  ..  Derek.


Hmmm. Now you've inspired me to dig out my Avo Meter. I actually found a battery for it, must buy that. 

Sent from my SM-A705FN using Tapatalk

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## ians

https://www.youtube.com/watch?v=b9hD...eElectricalGuy

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## ians

Derlyn ... please plug in your ELCB socket and polarity tester  (the one with 3 led lights) let us know what see.

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## ians

An important note.


https://www.youtube.com/watch?v=gr6Z...LEARNELECTRICS

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## Derlyn

@Ian
Gonna do some more testing tomorrow.
That was on my list of things to do.
Far from finished playing around with gennys. Too much that I still do not understand.

Vov is easy.

Disconnect the centre tap and connect the neutral to earth. Sorted.

These new gennys are not vov wound. They only have 2 thick wires from stator, namely live and neutral. There are about 6 or 7 thinner wires also coming out from stator. At this stage I don't know exactly where they connected or if they are connected to the stator, but I'm gonna carry on until I find out. Must have something to do with regulating the speed and voltage output.

Will keep you posted.
Derek

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Dylboy (28-Nov-21)

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## Sparks

I just saw the email with the original post. Check to see if the generator N and E are bridged.

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## Derlyn

Ok, some feedback.

Generator no load, only 2 lights on plug tester.

Opened generator and found the earth is floating. Hit in earth spike and earthed genny  ....   problem solved. 3 lights and earth leakage trips.

Disconnected earth spike, back to 2 lights on plug tester.

Opened genny and bridged neutral and earth. Connected to installation and tested. 3 lights, earth leakage tripped with tester as normal.

It seems safe to say that if the genny is NOT VOV then bridging the neutral and earth on genny is the answer, but first make sure that its not vov wound.

Interesting little exersize.

Will post some photos this evening.

Peace out  ..  Derek

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Dylboy (29-Nov-21)

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## Justloadit

If I am not mistaken, this falls under alternative load Earth/Neutral bonding wiring.

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## Derlyn

One or 2 photos. ( man of my word )



Floating earth




With earthspike. 3 lights.





My earth/neutral bridge ( yellow lugs )





Testing in kitchen with genny.


We modified 2 genny's today. The one was the Ryobi 6900 and the other was a Fragram 5 GFD-3  5kva.

Tips.  The wiring coming from the stator are not wired the same in these 2 models, so you need to make sure which one is being used for the neutral by removing the control panel in front.

I will carry on checking different gennys, but it seems to me that anything 5kva or bigger is not vov, but one still needs to confirm.

Peace out  ..  Derek

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Dylboy (29-Nov-21)

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## Dylboy

That is great ! Thank you for the pics. Nice to learn a bit more on the genny side.  :Smile: 

Having a thought (can be dangerous when i have a thought haha)

Instead of opening up the stator and doing what you have done , could it be possible to take the output of the genny and then bond the Neutral and the Earth to the earth spike ?

Now there are the gennys that have the centre tap and some not so not sure if it will work for both.

In my opinion it will work bar maybe the centre tap earth, but I would have to experiment unless a wise person on here knows.  :Smile:  

Why I am having this thought is just for warranty stuff as opening the stator may void warranties and all.  :Smile:  

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## Derlyn

> That is great ! Thank you for the pics. Nice to learn a bit more on the genny side. 
> 
> Having a thought (can be dangerous when i have a thought haha)
> 
> Instead of opening up the stator and doing what you have done , could it be possible to take the output of the genny and then bond the Neutral and the Earth to the earth spike ?
> 
> Now there are the gennys that have the centre tap and some not so not sure if it will work for both.
> 
> In my opinion it will work bar maybe the centre tap earth, but I would have to experiment unless a wise person on here knows.  
> ...


Hello Brother

Bridging the neutral and earth will work on a vov wound, BUT the centre tap must first be disconnected otherwise you are basically shorting out one half of the stator coil and the genny wont last long at all.

Peace out   ...   Derek

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Dylboy (29-Nov-21)

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## Dylboy

> Hello Brother
> 
> Bridging the neutral and earth will work on a vov wound, BUT the centre tap must first be disconnected otherwise you are basically shorting out one half on the stator coil and the genny wont last long at all.
> 
> Peace out   ...   Derek


Ah yes of course, Thank you ! 
So in the end it would have to be opened anyway to verify. Either way really enjoyed this post.



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## Derlyn

Dont need to open to confirm. Just run the genny and check voltages with meter. Vov will give 115 between neutral and earth and 115 between live and earth, a 50/50 split, then you know its vov.

Peace out  ..  Derek.

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## Dylboy

Ah yes true to that too, that is the first test I would do anyway prior to opening. Either way the customer will be informed of what would need to happen and get permission if opening up is required. 

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## ians

The solution is simple ... signage and awareness ... you cant do any more that that. 

I install the generator plug point at the meter use the correct equipment (correct size wiring ... circuit breakers ... changeover switch ... IP 65/7 enclosures and lable label and label) then attach a note to the email with the relevant information with regards to V-O-V ... max generator size for the applications and wait for my payment notice.

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