Coiled PV cables vs cut to min length..........

ligwyd

Hi there guys,

Just had a question I thought would be good to post here.....

I've got a high high voltage array with two strings of 9 panels each. The PV cables on the panels are approx. 3' to 4' long each. With a string of 9 panels that would be approx (if using 3' for calc.) 48' of extra unnecessary 10 awg PV cable in that string.....

I was thinking of cutting off the MC4 connectors, cutting the PV interconnect cables to min length, and then re-crimping on connectors, if that would, to any significant degree, increase the DC efficiency.

With higher voltage, the extra cable length is not that big of concern, but none the less, would that be a worth while effort or a waist of time and MC4 connectors?

I guess I could try it see if it does increases output.......

Just curious as to what others here have found or can offer to this topic before I do........

Thank you for the feedback

John

Vic

Hi John,

It is generally believed,  in these parts, that cutting off the factory-supplied MC, PV cable connectors,  will VOID the warranty on the PVs.

Unless the PVs in question are old and beat,  would suggest against cutting them off.

FWIW,  Vic

littleharbor2

 I agree with Vic regarding warranty issues. If you're not concerned about a warranty voidance I think it can make for a clean looking install. Is the backside of the array visible? 
 If you do this be very careful to disconnect the array AFTER the loads have been shut down and remember that you can't turn off panels so be careful to cover them and even work at early morning or late in the day.
 Do you have experience with MC-4 crimping? There's a bit of a learning curve in keeping the male and female parts where they belong. Once you snap the body over the contact there's no taking it apart. If you get it wrong you must cut the whole thing off and start over. Also be sure you don't crimp the male and, opposite mating, female in reverse. I came across this scenario once and it made for a pretty confusing troubleshooting session. Seemed like a simple correction but it turned out to be more involved than I thought, at first.

ligwyd

Agreed. I'll leave them alone. Just curious how much more efficient it would make the DC with nearly 50' less cable length?.....Maybe in the future I'll buy panels with short PV cables, if I can find them........

littleharbor2

ligwyd said:

Agreed. I'll leave them alone. Just curious how much more efficient it would make the DC with nearly 50' less cable length?.....Maybe in the future I'll buy panels with short PV cables, if I can find them........

I don't think it would be worth the effort aside from an aesthetic improvement. If it's not visible it would be a pain to do the swap for very little gain, if any.

The reason the cables are the length they are is so that they can be oriented in landscape fashion. If they were shortened then portrait fashion would be your only option.