Wiring Diagram Help Please

[kzano31]

This forum has been amazing the last few months as I've planned my build. I've searched through it more times than I can count and it seems like the deeper I dig into electric the more confusing it gets - I was hoping those with a lot more experience may be willing to review my electric diagram and help me correct all the things wrong with it.

The solar input for the Kisae 1250 is maxed at 50voc, 30amp. I can't run the four in series as it would be 108v and I can't run in parallel as it would be 31.2amp. My understanding is that if I run a series-parallel configuration the combined load would be 43.2v (from connecting a pair in series) and 12.48 amps (the connecting those two pairs in parallel). That would give me 10AWG at 20 feet?

I'd really appreciate the help, thank you!

[rowiebowie]

Welcome to the forum kzano31!

I'm not the expert you need, but I'm sure someone will come along. In the meantime, the series-parallel setup sounds like it should work.

[booster]

Originally Posted by kzano31

This forum has been amazing the last few months as I've planned my build. I've searched through it more times than I can count and it seems like the deeper I dig into electric the more confusing it gets - I was hoping those with a lot more experience may be willing to review my electric diagram and help me correct all the things wrong with it.

The solar input for the Kisae 1250 is maxed at 50voc, 30amp. I can't run the four in series as it would be 108v and I can't run in parallel as it would be 31.2amp. My understanding is that if I run a series-parallel configuration the combined load would be 43.2v (from connecting a pair in series) and 12.48 amps (the connecting those two pairs in parallel). That would give me 10AWG at 20 feet?

I'd really appreciate the help, thank you!

Pic is too small to read, but what you say would indicate 4 panels with max current of 6.24 amps and open circuit voltage of 21.6v, which is typical of 100 watt panel. That would be wired series parallel or parallel series.


Be sure the specs don't have varying ratings for currents, voltages, and watts of panel. Some controllers will have different panel watt maximums based on the type of panels and voltages and currents.

[kzano31]

Hi rowiebowie and booster, really appreciate the comments. I'm attaching a pdf in the hope that it may be more clear.

The Kisae 1250 limits input to 50voc/30A and for 12v panel input around 500W, but suggests an overdrive of 20% for a total of 600W. To get around the limitations I think I need to parallel series as it would only bring me to 43.2v and 12.48 amps. Do I then need to fuse each panel or would a single circuit breaker suffice? Thank you so much!

[booster]

Originally Posted by kzano31

Hi rowiebowie and booster, really appreciate the comments. I'm attaching a pdf in the hope that it may be more clear.

The Kisae 1250 limits input to 50voc/30A and for 12v panel input around 500W, but suggests an overdrive of 20% for a total of 600W. To get around the limitations I think I need to parallel series as it would only bring me to 43.2v and 12.48 amps. Do I then need to fuse each panel or would a single circuit breaker suffice? Thank you so much!

You may hear some that say a fuse on the panels is needed, but in reality the panels can't produce more than the 12.48 amps so even a 15 amp would never trip anyway. Others would say you still could get a short to ground and generate enough heat to cause an issue. But, of course you could still get 12.48 amps to ground if you fused at 15 amps, and you can't really fuse less than that because you need the power. Definitely fuse on the battery side of the controller.



I have seen a lot of systems without fuses, probably more than with, but probably isn't horrible either way.

[GeorgeRa]

You could consider a switch or a switchable CB between panels and controller. See the page from my Morningstar MPPT charge controller manual.

[booster]

Originally Posted by GeorgeRa

You could consider a switch or a switchable CB between panels and controller. See the page from my Morningstar MPPT charge controller manual.

Yes absolutely a switch on the panels so you prevent damaging things if the battery is disconnected. You should never have panels connected with no battery in the circuit.

[GeorgeRa]

Originally Posted by booster

Yes absolutely a switch on the panels so you prevent damaging things if the battery is disconnected. You should never have panels connected with no battery in the circuit.

If I would be doing my solar again I would likely add a double switch to instantly switch off a controller on both sides.

[booster]

Originally Posted by GeorgeRa

If I would be doing my solar again I would likely add a double switch to instantly switch off a controller on both sides.

I think you would need to do it with a break/make type delay switch like Blue Sea has for some of their battery switches. The built up voltage on the panels could be and issue as the battery stability probably takes a tiny bit of time.

[kzano31]

These replies are extremely helpful and I appreciate the expertise and advice. I’m going to add switches so the controller can be easily turned off and fuse on the battery side of the controller.