Where to mount Midnite MNPV6-250 combiner?

[MJSullivan]

I am about to order a Midnite Solar MNPV6-250 combiner box with which I plan to combine two PV strings together. To this box I will also add a Midnite MSSPD-300-DC surge protector. Given that there are two breakers inside the box, it seems to me one would want to be able to have easy access the box in the case of tripping the breaker. OTOH, to reduce issues with surges and reduce the length of the separate DC runs, I imagine one would want the combiner as close to the PV panels as possible. To wit: I have seen quite a few pictures of similar combiners located on the roof of the house near the PV panels. In my particular situation, gaining access to the roof will be a major pain. Instead, I was considering adding a QBox junction box on the outside near the PV panels and then positioning the MNPV6-250 combiner box inside in the attic space near the QBox -- gaining access via the attic will be much easier for me. Any issues with that setup?

Thanks!
Michael

 

[MarkSolar]

I would just buy enough PV cable to extend the panel leads down to some place really convenient for the combiner, like on your garage wall or even the outside wall. If you're talking 100s of feet that's one thing, but if you're talking 25' I wouldn't even think about it. You can order premade cables from Home Depot online if you're not close to a real solar type place.

 

[anadiner]

I would just buy enough PV cable to extend the panel leads down to some place really convenient for the combiner, like on your garage wall or even the outside wall. If you're talking 100s of feet that's one thing, but if you're talking 25' I wouldn't even think about it. You can order premade cables from Home Depot online if you're not close to a real solar type place.

The garage idea is appealing. Depends on how his wires r ran in. Like u said tho, get enough cable to go where u want.

For me, having experienced my house burn completely and kill my pets, Im only comfortable with combiner on outside... can be below panels... definitely cuz 250. Ground panels, c box and disconnect. Thats me do I can sleep at night.

 

[MJSullivan]

The garage idea is appealing. Depends on how his wires r ran in. Like u said tho, get enough cable to go where u want.

For me, having experienced my house burn completely and kill my pets, Im only comfortable with combiner on outside... can be below panels... definitely cuz 250. Ground panels, c box and disconnect. Thats me do I can sleep at night.

That is very interesting.
Why would a combiner be a weak point in a PV system?
Lightning strike perhaps?

Michael

 

[rhino]

First thing that comes to my mind is all the roof top fires in Australia due to a safety requirement of adding a DC isolator switch on the roof but turns out a lot of the switches are causing fires themselves. This on top of a lot of poorly installed roof top systems there has caused a black eye and people being weary.. I've not heard of any issues with the Midnite combiners and they are also all metal unlike some others. The manuals for the Midnite combiners even show them being installed on a roof as long as it has at least a 3/12 pitch.