Online assistance for electrical trade people in New Zealand and Australia Login  |  Register  |   Forgot Password
Assistance for electrical trade people
 

 

 

 


Click here to send Ron a pdf document for publication on this Topic

Documents must be less than 200k in pdf format

Posted By Topic: PV ac & dc Cables

nalla
Apr 02 2019 07:31

some advise need
Im doing an inspection on a PV system with batteries. The sparky has installed a PVC trunking along the wall under the investor and Battery control equipment. He has all the cable in this trunking.
Recently I read the DC cables cant be in the same enclosure as AC cables. Can I be pointed to this. Ive done some searching but Im full of the flu and not concentrating that well
   

pluto
Apr 02 2019 07:45

All cables need to be insulated for the highest voltage AS/NZS 3000:2007 clause 3.9.8.3.
   

Someone
Apr 02 2019 20:15

I can't find anything requiring separation in 5033 either.

It does need to be proper PV cable though; NZS5000 TPS (circular or flat) is not acceptable.
   

AlecK
Apr 03 2019 09:11

That relates only to the array cables. For wiring associated with batteries, and not exposed to intense UV or operating at temp well above ambient; normal cable is perfectly fine.
   

pluto
Apr 03 2019 11:59

PV array cable has a higher voltage rating greater than AS/NZS 5000.1 cable which stop at 1000V

PV array cable has a 1200 V (approx) rating ideal when the PV array is operating at 1000 volts, which is possible in commerical systems. Only one cable type is used for all systems.

Ambinet temperature and UV exposure are NOT the main reason.
   

AlecK
Apr 03 2019 14:08

Obviously needs to have a suitable voltage rating; although there's absolutely no reference to that in 4.6.3 of currently-cited edition.

There's also no specific requirement to use special "PV" cable; whatever that may be.

There IS a clear Note referring to UV & operating temp. i didn't say they were the only considerations, but they're certainly relevant when deciding what cable to use.
Or more relevantly (since this is about inspection), whether the cable used by the installer complies.



2014 edition does specify Standards that some - not all - LV array cabling must comply with; but that's NOT enforceable until cited by ESRs. The requirement doesn't apply to non-array cabling, eg battery cabling, as it's out of scope for the Standard.

And it doesn't apply for ELV cabling at all.

So not true to say "only one cable type is used for all systems". That may be preferred, but it is not a requirement.







   

pluto
Apr 03 2019 20:35

AS/NZS 5033:2014 clause 4.3.6.7 (i), (ii) and (iii) contains the PV array cable and type numbers from 3 countries
   

nalla
Apr 04 2019 06:48

Thanks for the help
I think this goes to show how problematic it can be inspecting when unsited standards are out there.
This is my second real issue in as many weeks inspecting PV systems
The other an inverter install issue and was using the AS4771.2005. A document so far behind technology its a joke piece of paper
   

Dufresne
Apr 04 2019 08:27

Hi Pluto

Looking at AS/NZS 5033-2014+A1&2 I cannot find clause 4.3.6.7. Is that reference correct?
   

pluto
Apr 04 2019 08:43

correction quoted clause should read 4.3.6.2
   

AlecK
Apr 04 2019 09:11

Outdated or not, inspections required by ESR 70 MUST be to the relevant cited Standard(s).

Which for this case currently would be
- AS/NZS 3000: 2007 +A1+A2 & as modified by Schedule 2 of ESRs
- AS 477.1: 2005
- 5033:2012; as modified by Schedule 2 of ESRs. (good luck finding anything that complies with the wording of the citation amendment!)

True technology on many fronts is developing rapidly, and standards are playing catch-up. But the new technologies can still be used, provided the way they are used does not conflict with the currently-cited Standards.
As Inspectors, it's our job to keep clearly in mind that we can't "fail" on the basis of non-compliance, unless it's with the currently cited rules. And where the is a conflict, we can't "pass" a new technology that doesn't meet the existing requirements.