Cable calculations

[Blue Duck]

Good morning,

Installing some inverters for a pv install, output of the inverters is 40a, installed 10mm h07 5core on tray from  ac isolator to pv panel, been told this is wrong and needs to 16mm because of a grouping factor of 0.68.

Don't have regs on me but thos doesn't sound right to me !

Help! 

 

[Spoon]

Depends on a few factors.

Best you have a look and see what your install is.

 

[Evans Electric]

You may be OK with that  as the design load is 40A    , flex rated @  49A  .  Is it buried on the tray or in free air ?       Has someone done the calcs then  or just guessing ? 

 

[Blue Duck]

We've decided to use 16mm armoured as the consultant won't budge.

We have been asked to do some odd things on this job to satisfy the client.

Lots of over sized cable, awkward cable routes etc etc.

Thanks for your input! 

 

[Barx]

Bear in mind that PV has stricter volt drop requirements too

 

[binky]

1 % for PV 

 

[Blue Duck]

Bear in mind that PV has stricter volt drop requirements too

1 % for PV 

Cheers guys!

The consultant has relented! It took the director of the main contractor to point out the error of his ways! :lol:

The inverters are < 4m away from the panel, so we didn't feel volt drop would be an issue.

250kw E/W system using solar edge kit, near completion, next one is a 350kw system!  :Godno:

 

[binky]

point out Solaredge is a waste of money..... :lol:

 

[Blue Duck]

Yes I agree, but its got all the bells and whistles and idiots like bells and whistles.

I have to go look at another 250kw solar edge system that's faulty, I suspect spiders in the the optimizers, may have to hit you up for some advice on that one... 

 

[Sharpend]

Remove them? :C  

 

[binky]

Yes I agree, but its got all the bells and whistles and idiots like bells and whistles.

I have to go look at another 250kw solar edge system that's faulty, I suspect spiders in the the optimizers, may have to hit you up for some advice on that one... 

it'll cost you  Guinness

Remove them? :C  

that means lifting all the panels and replacing the inverter.

 

[binky]

may have to hit you up for some advice on that one... 

The inverter should display how many optimisers it can see, so if you can see 16 out of 30, then fault is about half way along the string.  NB the optimisers output 1v in shut down, so 15V is 15 optimisers etc etc Trouble is some of the newer inverters don't have a display... so you wil need app or laptop. If you are lucky the installer regsitered the array on the portal with a full map of the optimiser numbers and their locations, and this should tell you where any faults are.  It's quite a clever system, but as I have said many times, it introduces twice as many failure points to the array, ie twice as many connectors, which is why I don't like it. Always worth doing an optimiser re-boot - be warned linking the final few optimisers can take a while - set it going and make a brew  :^O . 

Let me know how you get on, I'm a bit rusty on Solaredge hot having fault found 1 for a few years.

 

[Barx]

Most Solaredge issues I've dealt with are the inverter not ramping up. i.e it will power up and show screen but not actaully talk to the optimisers and tell them to start powering. Solaredge technical can 'reset' something from their end and get it going again. That is, so long as the gateway connection is active.