Junction Box

**Soulbringer** · August 23rd, 2007, 0:58 PDT

Hello

I want to install 24 kW photovoltaic system. I bought inverters (SMC8000TL) and solar panels. So I just have to connect them to the grid (380V/50Hz). From the AC side of Inverters to the Junction Box i have 3 mono phase cables. I put them throught 3 fuses 40A and then on the exit of fuses I put 3 phase cable for 380V. So the question is what is better to use 1 pole fuse( for each cable) or 3 pole fuse (I=34.78A). Does anybody can show pics of some already install Junction Boxes.

Best Regards

**Solar Guppy** · August 23rd, 2007, 6:49 PDT

400V / 24kw / Three phase is at a minimum a job for a licensed electrican, NOT a do it yourself job with info off the internet. Anyone even thinking of providing information would be putting people in harms way ...

You will need to be signed off by your local jurisdiction, I'm sure they will require properly certified professionals to have installed with permits so start there for your questions

**mike95490** · August 23rd, 2007, 6:56 PDT

24KW is an ambitious system, and beyond the scale of anything I've seen. Good luck to you.

My gut feeing is a fuse on each leg, where it connects to each inverter. Of course it's got to have it's proper enclosure and such.

**Roderick** · August 23rd, 2007, 11:32 PDT

Hello,

With utmost respect, I'd suggest that if you bought 3 x 8 kW inverters, and appropriate solar panels to match, that the extra money to pay a professional to hook it up will be small in comparison. You can save money by doing the physical install of the panels yourself, or with your own people, then let the pro do the electrical, at least the AC side.

If you are still in the planning stages and have not bought anything yet, that's even better, because engaging a consultant to at least crudely specify array layout, sizing, and components could actually save you money over just buying things and trying to make it all work later.