Please Help!! Starting new job tomorrow!! Testing PV

[Blank]

Hi there, this is my first post so please go easy on me!! Grin.

I start a new job tomorrow after being unemployed for almost 12 months, I only found out that I had the interview today or I would have found out the answer to my question before now and not left it to the last minute. I so want to make a good impression.

I do have my 2391, but the following has confused me.

I think its quite a simple question if I can explain it properly, so here goes.......

The wires from the solar panels feed a double pole DC isolator in the loft, this isolator feeds the inverter.

The inverter feeds a double pole AC isolator which is also in the loft. This isolator feeds a monitoring unit in the mains cupboard in the house, this moitoring unit feeds a lockable double pole AC isolator, which inturn feeds a new 1-way mains unit which is positioned next to the original house consumer unit.

My questions are as followed....

Do I take my Ze at the inverter or at my new 1-way mains unit?

Do I take my Zs at the inverter or at my new 1 way mains unit?

Do I take my Pefc and Pscc at the inverter or the new 1-way mains unit?

Im guessing it doesn't mater which end I do my R1 + R2 or my Insulation resistance. Spose im confused because the electricity is all going backwards!! Ha! Ha!

Thanks in advance, if you can get me the answers by 7am tomorrow morning then I owe you a night in the pub!!

Blank.

 

[kme]

If you haven`t done the PV course, and aren`t sure what tests to do on the DC, I`m willing to bet you don`t have the necessary test gear to carry out the required tests.

Sorry to doubt you, but if you DO have 2391, and are asking questions such as this regarding Ze and Zs, then there isn`t much hope for humanity anymore.

The DC will kill you if you get it wrong - dependant on config, there could be 900VDC on the end of the wires. Try not to die. Good luck

KME

 

[Blank]

Thanks for your concerns KME. I did do the PV 2372 course about 15 months ago, but ive never done any PV work.

I do understand the dangers of solar panels being permanently live.

The company who have enployed me have all the relivant testing equiptment and I will be working with another electrician (who will be in charge) for a week or so. I was just looking for a few pointers so I could make a good impression on my first day thats all.

All the best,

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[lineman]

Not done the pv course myself mate buy frequently install the AC side. Testing is the same as any other new submain install if a new board is fitted when there are no spare ways on the main cu. Ze and PFC done at the incoming and zs and r1+r2 at end of line before the inverter. And always notifiable as it is an introduction of a new circuit.

 

[Blank]

Thankyou lineman!

The thing which was confusing me was I wasn't sure if the new mains unit was the end of line or the inverter was the end of line.

Perhaps I am a bit of a village idiot.

The company is regested with the NIC I beleive.

Thank you for your help.

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[ProDave]

As KME says you need to UNDERSTAND what you are doing.

I'm no PV expert having not done the course and only installed 1 system, but I know the principles.

The DC side, as well as being always live (in the daylight at least) is DC. If you accidentally grab hold of 900V DC it's far more likely to kill you than AC, that's because a shock from DC is more likely go grab you, whereas a shock from ac is more likely to throw you off.

I do hope you wont be going straight out on your own, and will have someone to help you for the first few installs, in other words, I hope you haven't bitten off more than you can chew.

It does sound like you have blagged your way through the interview, without really knowing what you have let yourself in for.

 

[kme]

Also be aware of the disconnection time requirements - I note Lineman mentions "spare ways" in an existing board. ; however, under most setups, this will lead to the disconnection time being exceeded for pre-existing circuits.

 

[steptoe]

Im sorry

headbang