6 - String Solar PanelCombiner Box MC4 Connectors

[dgdistrb]

Does anyone have suggestions about using this box with my system? I have 6 - 150W - 12V Panels, going into a 60A Xantrex Charge Controller.PWN.
http://www.ebay.com/itm/6-String-Sol.../142133157123? ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m14 38.l2649

[littleharbor]

I don't see any fusing or breakers. Should have these with anything over 2 strings. This one is much better and the same price.

http://www.ebay.com/itm/6-String-Solar-PV-Combiner-Box-W-Circuit-Breakers-for-100W-Solar-Panel-System-/253082718677?hash=item3aece7d1d5:g:WM8AAOSwA3dYJA6i

[dgdistrb]

That looks like a nice unit. I will have to look into that one.

[dgdistrb]

I have 2/0 aluminum wire coming in from the box to the house, going to a 60A fuse. I don't think this box can handle 2/0 wire.

[littleharbor]

You would need to transition from 2/0 aluminum to a properly sized copper conductor. Are you using such large wire because of a long run to your charge controller? If that's the case you should look into an MPPT controller and series wiring those 6 panels. In that case you wouldn't need a combiner box.
You wont get 2/0 aluminum into the C-60 either.

[dgdistrb]

Do I need a fuse or breaker outside for the solar panels? Or is my 60A inline fuse enough?

[dgdistrb]

I am using a reducer box now. I was hoping to eliminate it. Yes I used the large wire because of the long distance run into the house.

[littleharbor]

If you run all 6 in parallel you need to fuse all 6 panels, hence the combiner box. If you went with a series string and MPPT controller you wouldn't need fusing. usually you would have a breaker between the input to the CC and between the output to the batteries.

[dgdistrb]

I cannot go with an MPPT at this point. But I will go with the type of box you showed me. I will keep my reducer box if needed.

[SunEagle]

I cannot go with an MPPT at this point. But I will go with the type of box you showed me. I will keep my reducer box if needed.

Just make sure that box is rated for your total panel wattage. I thought it stated it would handle 6 x 100watt panels (600watts) and you mentioned 6 x 150watt (900watts).

[littleharbor]

Just make sure that box is rated for your total panel wattage. I thought it stated it would handle 6 x 100watt panels (600watts) and you mentioned 6 x 150watt (900watts).

Good catch, I don't see a higher rated version. It says 10 amp circuit breakers but shows touch safe fuse holders. Midnite Solar has some inexpensive combiners but they don't have MC-4 inputs.

[SunEagle]

Good catch, I don't see a higher rated version. It says 10 amp circuit breakers but shows touch safe fuse holders. Midnite Solar has some inexpensive combiners but they don't have MC-4 inputs.

The individual fuse holders for each panel should be rated high enough for the Isc rating of the 150watt panel but you need to check the fuse to see if it is high enough.

The other over current device is that 60amp 2 pole CB. That needs to be high enough for the total Imp rating of all six 150w panels x 1.25. It is probably rated for six 100watt panels but it may be enough depending on the Imp rating of your 150w panels x 6 x 1.25.

[littleharbor]

The individual fuse holders for each panel should be rated high enough for the Isc rating of the 150watt panel but you need to check the fuse to see if it is high enough.

The other over current device is that 60amp 2 pole CB.

Absolutely, I searched and couldn't find a model with anything other than 10 amp fuses. The specific fuses for those holders aren't cheap though. Then the 60 amp breaker would need to be replaced if you did , in fact, use all 6 inputs. Nice combiner otherwise.

[bcroe]

Absolutely, I searched and couldn't find a model with anything other than 10 amp fuses. The specific fuses for those holders aren't cheap though. Then the 60 amp breaker would need to be replaced if you did , in fact use all 6 inputs. Nice combiner otherwise.

Generally those high voltage DC fuses are quite pricey. Some time ago I saw some PV in line fuse holders on Eval Bay
which included a 15A fuse. I asked if they could send them with 10A fuses instead, and they did. Bruce Roe

[SunEagle]

The fuse holders in my combiner box are rated 30A each but I use 8amp fuses which aren't cheap but less then DC circuit breakers.