Saturday at home, installing an inverter

[tec0]

Oasis II 324 3KVA 24V Pure Sine Inverter with intergrated 40A battery charger (1)
Oasis Single Phase Bypass Box (1)
Trojan T105 - RE 225Ahr @ C20 6V Wet Cell Battery (4)
250W A-Grade Solar panels (6)
Outback 60A 12/24/48V MPPT Solar Regulator (1)

total price about R77k

i phoned a few other companies see if i can get something a bit more cost effective.

[natal21]

Oasis II 324 3KVA 24V Pure Sine Inverter with intergrated 40A battery charger (1) 3Kw pure sine wave bi-dirctional inverter with 60A charger R18 357.14
Oasis Single Phase Bypass Box (1)maybe R2000
Trojan T105 - RE 225Ahr @ C20 6V Wet Cell Battery (4) 2x12v 170 Ah lead crystal @r5400 each R10800
250W A-Grade Solar panels (6)6xR2350=R14100
Outback 60A 12/24/48V MPPT Solar Regulator (1)approxR4000-R5000

total price about R77k Total R50257 approx not including connections and cables and labour or roof mountings etc.

i phoned a few other companies see if i can get something a bit more cost effective.

hope this helps

[SilverNodashi]

hope this helps

Those prices seems fair. Some places will charge more though.

[tec0]

It is crazy that "ALMOST" no websites have prices when it comes to solar stuff. I am looking for a reasonable system at a reasonable price. R70k R60k and R50K is not reasonable. Here is the thing our Proudly South African Products is all but missing. I have spend the last week trying to get hold of locals. Because we are told that we must support our local businesses/fabricators...

The most i am willing to spend is about R20k to proof concept because there is no way in hell, i am going to spend R70K and have no other information other then "it is a big system" It is like buying a new car because the wheels are shiny...

I want to know -> maintenance cost, parts cost, General problems with the system because we need to know. But because that info is classified as beyond secret we just have to bite the bullet and test stuff out. Now i am not willing to to spend seven month's income on a whim...

[IMHO]

tec0, I feel you. Most of these also make obvious ridiculous claims, resulting in one not believing the little info they do give.

Look at the system advertised below. If run at 6KW , it will not last an hour, but they claim up to 8 hours. Total BS and misleading.

[vieome]

http://www.donrowe.com/power-inverter-faq-a/258.htm

How long will battery last

[Justloadit]

No one gives this information out, because of 2 reasons, one, is that they do not know what the are selling/supplying, they simply jumping on the band wagon to make a quick buck, and secondly, the ones that do know do not want to burst your bubble, when they advocate free energy!

There is a maintenance cost on batteries, it depends on usage, and how deep you regularly discharge your batteries. However, solar panels should last over 15 years. Inverters are like any electronic device, it depends on the manufacturer, and the quality of the components. The more serious the manufacturer, the higher quality goes into the product, and of course becomes more expensive. The China Mall stuff is cheap and nasty, and I caution customers to avoid it if they possibly can.

Issuing verbal warranties, has about as much value in it as in nothing. Many suppliers use the so called factory warranty as part of their spiel, but ultimately, who carries the warranty? The supplier, as the manufacturer simply says to send the equipment back to China for repairs, the cost of transport over passes the cost of the equipment, so effectively you as the customer losses out.

The stuff I sell, I can repair in house, and therefor, has a limited warranty which I provide in case of premature failure.

When it comes to batteries, I give no warranty, simply because the battery manufacturers do not give any warranties either. The reason for this, is that a manufacturer can not deduce from simply looking at the battery what the customer has done. Over charged? over discharged? mishandled by customer? just far too many unaccountable variables.

I do get my batteries from a reputable supplier, and to date have gotten reasonable service out of them.

[AndyD]

As with all items it's not a case of 'don't buy Chinese' it's a case of know what your buying and stick to the brands that are already proven reliable by their track record. Unfortunate price isn't always an indicator of quality especially in the unstable market climate we're in of everyone jumping on the UPS/inverter/solar bandwagon and a large proportion of the suppliers that have appeared on the scene will hit and run and not be around for the long haul.

We've traditionally installed critical systems backup in the larger commercial and industrial market and the equipment is high-end but out of budget for the domestic and small business market that's recently exploded in demand. We've been looking for a cheaper product which is more basic but still reliable.

Realistically most of the customers looking to reduce the effects of load shedding are not interested in many of the features the high-end products offer, they're not looking to connect PV panels, wind turbines and they don't need reports and monitoring etc, they're also not in need of the scaleability, they're just wanting selected appliances running for a few hours of power outage.

We've installed a dozen or so of the Axpert inverters to date and so far they've performed well in the field so we'll continue to offer them as a budget option. The thing I like about them is that whilst they're somewhat dumbed down in features and flexibility they have a good range of units that offer different features and sizes etc and they're available from solid suppliers who can provide technical back-up and will honour their warranties. They won't cover every application we get requests for but that's also fine, if we can't apply them as a solution I'm happy to decline the customer.

The biggest problems I've encountered is some of 'one size fits all' products around where it's sold as a complete system preassembled in a box. Some of these are being grossly mis-sold with their capabilities being obfuscated by stating their run time at a certain percentage of full load in the small print. I've had a couple of customers who've opted for one of these and on both occasions they paid less for the entire system than our quoted price for just the batteries on the system we designed for their needs. Needless to say it didn't end well, both are incapable of running for over an hour even though the salesliterature on both systems convincingly states they're capable of a 3 hour back-up time. One of them was especially impossible to determine the capabilities, they used a formula that assumed peak load for 5% of the time,75% load for 10%, 50% load for 30% of the time and 25% load for the remainder. No hard info on the capacity or the type of the batteries was stated anywhere so how anyone is supposed to design a system with this unit is completely beyond me.

I feel for you Tec0 but as a designer and installer I'm in as much pain as you are.

[IMHO]

How long, in years, can a battery last? The Deltec 1250 claim 2000 cycles at 10% DOD. If one is using it strictly for power outages say 3 times a week at less than 10% DOD, you will cycle it 156 times a year, which means you should be able to do it for 12.8 years. (2000/156).

Is this possible? Is the battery not going to pack up before that from age alone, never mind the cycles?

I suppose it could be possible if you do maintenance on the batts, but you cant, as it is sealed units.

[IMHO]

Can one check DOD by taking the volt measurements of a battery? My Deltec 1250 is fully charged at 13.1 volts. What should the volt readings be at 50%, 20% and 10% DOD?

[AndyD]

Yes, the depth you cycle you battery to will have a pronounced effect on the number of cycles in it's lifespan. Most batteries have predictive lifespan graphs available from the supplier where you can predict the number of cycles your batteries will survive and, from experience, they're fairly accurate if you're using a good charger and perform very basic maintenance.

13.1 volts sounds a little high, usually fully charged is just under 13 volts and the 50% discharge voltage is around 12.1-12.2v. Gel batteries are usually a little higher voltage that lead acid though. Using voltage to check battery charge is prone to innacuracies if the battery has been under recent charging or load conditions and temperature can also have small effects on the reading. You should never discharge a deep cycle leadacid battery below 12v as a rule of thumb which will by 75% discharged at that point. Also try not to leave the batteries in a low state of charge for any length of time, obviously if you're only using solar or wind to recharge them it might be unaviodable but in that case select batteries accordingly.

[bergie]

i see the axpert default cut off dc voltage is 21 volt on the 24 volt 3kva. the 48 volt 5 kva default setting is 42 volt. i wonder why they set it so low.

[vieome]

It is crazy that "ALMOST" no websites have prices when it comes to solar stuff.

I have always wondered why a lot of websites never put prices for their products. In a sense you end up wasting a potential customers time and company time, as they have to email or phone for a price.

On another note
High demand has pushed up inverter and battery prices, but as more suppliers join the market(in hopes of making super profits)it will lead to a decrease in price.

During power cuts my only need is lighting(gas stove). I bought a cheap chinese inverter 100W(R100) 50amp Battery (R800) Battery charger(R350) and runs three 11W lamps for about 7 Hours. Being using the setup for about 2 months now(Twice a week).

[Justloadit]

i see the axpert default cut off dc voltage is 21 volt on the 24 volt 3kva. the 48 volt 5 kva default setting is 42 volt. i wonder why they set it so low.

This is so you get the so called time of operation on the brochure. Following this route means that after approximately 30 cycles, your battery is dead.

I have had a problem with one of my customers, precisely because of this. He reckons the China Mall Solar inverter and charger is better than mine, because it runs for 2 hours longer than mine. What he does not understand is that my unit cuts out at 11.5V thereby prolonging the battery lifespan, as opposed to the competitive unit cutting out at 10.5V. I am now waiting and hoping for him to come back after his battery is dead and reverse his statement.

[Justloadit]

How long, in years, can a battery last? The Deltec 1250 claim 2000 cycles at 10% DOD. If one is using it strictly for power outages say 3 times a week at less than 10% DOD, you will cycle it 156 times a year, which means you should be able to do it for 12.8 years. (2000/156).

Is this possible? Is the battery not going to pack up before that from age alone, never mind the cycles?

I suppose it could be possible if you do maintenance on the batts, but you cant, as it is sealed units.

The majority of batteries have a 5 year lifespan, unless you specifically look for and purchase a long life battery. You guessed it, cost is far much higher.

With respect to measuring the battery capacity, it is possible, but you require some very expense electronic equipment. I have been looking for one for a while, and found one at RS. ACT Battery Tester