# Interest group forums > Energy and Resource Conservation Forum >  Solar panel wiring. (Question)

## Derlyn

Can one use FTE between panels on rooftop and controller downstairs in place of solar panel wire ?

6mm FTE costs less than 6mm panel wire and makes for an easier and neater job.

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## Isetech

Is it double insulated and rated for the correct voltage?

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## GCE

You will need to use PV cabling between the panels , not panel wire .The weather place havoc with panel wire .

You could use Surfix , due to the screen, inside the roof space and ensure that it is labelled as DC wiring - Surfix is rated for DC voltage 

We have brought the PV down to a joint box on the wall , joined to surfix and run the surfix in the rood space in a conduit against the underside of the roof tiles to keep them separate from AC wiring and label the conduit , DC wiring .

Have pasted a section from SANS 10142-1-2 that was published and then withdrawn - Gives you an idea as to what the thinking was 


_5.4.5.1 The DC system where applicable shall be protected against the effect of induced voltage
surges by, implementing of the following wiring measures:
a) keeping the DC cable as short as practically possible;
b) installing or running the positive and negative cables alongside each other, to prevent the formation
of induction loops;
c) the bonding conductors used to bond metallic parts in the array e.g. PV module frames, PV module
supports and wireways/trunking shall be run as close as possible alongside the live conductors of
the array; and
d) using screened/armoured cables, or to installing the cable in earthed, metal conduit/trunking where
the DC cables are greater than 5._

_B.15 Electrical metallic tubing, conduit and or cableways, shall be marked by a label such as the
one shown in figure B.11 in no less than every three meters, at every turn and above and below
penetrations.
B.16 Any additional markings and labels within the photovoltaic installation shall conform to the
requirements on SANS 1186-1.
_

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Derlyn (06-Jun-22)

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## Derlyn

> You will need to use PV cabling between the panels , not panel wire .The weather place havoc with panel wire .
> 
> You could use Surfix , due to the screen, inside the roof space and ensure that it is labelled as DC wiring - Surfix is rated for DC voltage 
> 
> We have brought the PV down to a joint box on the wall , joined to surfix and run the surfix in the rood space in a conduit against the underside of the roof tiles to keep them separate from AC wiring and label the conduit , DC wiring .
> 
> Have pasted a section from SANS 10142-1-2 that was published and then withdrawn - Gives you an idea as to what the thinking was 
> 
> 
> ...


Thank you, Brother. Much appreciated. Gonna have a bit of fun on my own house today.  :Wink:  :Wink:

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## Isetech

I cant speak from experience because I haven't done a PV install yet, but from the sites I have visited: 

Some have open double insulated flexible wires cable tied to the steel frame used to install the panels , then down the wall using PVC conduit (no labels) 

Some have PVC conduit from the panel, drilled through the roof, then saddled to the battens or across the roof down into the trunking with all the other cables, a mixture of mains, essential, non essential and even cat 5 cable all together. I am still waiting for the COC.

Some have the wires cable tied to the frame, then into a piece of steel copex, into steel P8000 trunking and down into a panel. 

Some have have the wires cable tied to the frame then into P8000 or P9000 depending on the size of the PV array,  all the way down to the panels.

If the wire is double insulated and UV protected do you need to install it in a wireway?

Does the wireway have to be PVC or steel out on the roof and the same inside the roof ? 

Can you install the earth in the same wireway ? 

Is an earth wire required from the panel down to the panel ?

If you fit a combiner box on the roof or close to the panels, do you still have to use double insulated wire from the combiner box down to the inverter?

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## Isetech

_It looks like we need to do another thread to highlight the requirements for markings and labels  Anyone keen to share? 

B.16 Any additional markings and labels within the photovoltaic installation shall conform to the
requirements on SANS 1186-1._

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## Derlyn

It's lekker when you are playing on your own pad. I have a combiner box with fuses at the panels. Decided to go with pv 6mm wire in conduit down to the regulator. Each panel has a 10 Amp fuse in the combiner box. Just before the regulator there are fuses on both the pos and neg which also serves as an isolator to the regulator.

I'm speaking under correction, but I think one only needs an earth if the supply to the installation is overhead, the same as a house with a conductive roof. Maybe someone can correct me if I,m wrong.

Anyway, it's new for me and I'm enjoying the project.

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## Isetech

> It's lekker when you are playing on your own pad. I have a combiner box with fuses at the panels. Decided to go with pv 6mm wire in conduit down to the regulator. Each panel has a 10 Amp fuse in the combiner box. Just before the regulator there are fuses on both the pos and neg which also serves as an isolator to the regulator.
> 
> I'm speaking under correction, but I think one only needs an earth if the supply to the installation is overhead, the same as a house with a conductive roof. Maybe someone can correct me if I,m wrong.
> 
> Anyway, it's new for me and I'm enjoying the project.


There are requirements for earthing and bonding for the panels. I will share as soon as I start with the PV planning for my projects. 

 I am so looking forward to starting the first Sunsynk inverter project, it will be going into the workshop for a couple of months to tinker, get the module  laser and fitted below the inverter so that you dont see any wires or sprag or any of that ugly stuff. I want all my installation to look like the one on the front page of the Sunsynk website. We are going to be spending some time on the steel fabrication and powder coating. 

We are also looking into locations and others way to install solar panels, instead of on the roof of the house. I have an idea at home to install a wooden structure to create a privacy shield which will also create a location for the panels. 

I have designed and installed a few Axpert inverters which have a piece that fits below to hide all the wiring. It becomes a bit of a challenge because you have to take the air flow, the on/off switch and the fuse button into consideration. 

I have the Fluke 435 recording all the V,A, KW etc, preparing for the reports so that we can work out the essential and non essential circuit for the 3 tier DB. Make sure that I understand the time of use maximum demands of all the appliances etc. 

I am like a kid with a new toy, spending months doing all the research into the installations, hence all the questions and posts.

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## GCE

> I'm speaking under correction, but I think one only needs an earth if the supply to the installation is overhead, the same as a house with a conductive roof. Maybe someone can correct me if I,m wrong.
> 
> Anyway, it's new for me and I'm enjoying the project.


Normally earthing is require as stipulated in SANS10142-1 and the frames of the panels and structure need to be earthed  
Remember you now have a supply coming from overhead

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