IIRC, member, Photowhit made his own PV Combiner ...
But, really, DIN-Rail DC breakers from MidNite and OB Power are very inexpensive, and the MidNite Combiners, which are made in many sizes, are also inexpensive, for what they include.
It IS possible to use Square D QO panels, with SQ D QO (NOT QOT) breakers, within fairly narrow constraints, in DC systems, with currents below 70 Amps, and voltages that are always below 48 volts. AND, this does not apply the HomeLine breakers, and probably not the HL panels, either.
BUT, practically, this really saves nothing. The SQ D subpanels have a Neutral Busbar, but only a single position ground lug, etc.
For very small 12 V or 24 V systems, this may be OK, with the real advantage of being available, often off the shelf at the BigBox store, seven days per week. BUT, the HD near here is often out-of-stock on some to the items that you would need in the SQ D QO line.
Of course some inspectors could have problems with QO hardware used in DC systems, but usually the only thing inspected on the DC side is equipment grounding, and perhaps Ampacity of conductors.
Breakers for DIN-Rail PV Combiners:http://www.solar-electric.com/installation-parts-and-equipment/midnite/cipr1/stfubr1/mnepv.html
AND, ws, just to be clear, a Combiner is usually only required when one has three or more strings of PV modules ...
FWIW, Opinions from Vic
6 or less lines to be combined?
Will fuses work for you?
Search eBay for Outback PV12
$100 delivered for a used Din rail box and 6 fuse holders with 15 amp fuses...
There's also a new 4 string box for $55 delivered, with fuse holders and 10 amp fuses, if you happen to have a friend who has a punch (no knock outs that I can see) search homerun combiner solar
Then you will want to search for the correct wire restraints since he pulled them.
http://www.solar-electric.com/installation-parts-and-equipment/midnite/pvarco.htmlwill this one accept 2/15amp break and 1 ground fault breaker and 3 more 30 amp breakers??? for 88$ I guess cant be beat..
The GFCI breaker set is intended to interrupt the output of the Combiner in the case of a Ground Fault. AND, assume that the two other 30 A breakers are intended to be the PB input breaker to the CC, and one on the CC output, none of these breakers will want to be commoned onto the Combiner busbar.
AND, it looks like you are thinking of the GFCI breaker as a single breaker. It is most often two breakers, with their handles connected together ... so this would add up to seven breakers, the way I count it.
How many parallel strings or parallel individual PVs do you want to combine?
While it is convenient to have breakers on every PV "String", it is not essential for "Strings" of two PVs.
There are also DIN-Rail boxes for indoor use -- the MN Big Baby box is the most useful for most of us. It has room for four DIN breakers. The Baby Box and Is usually too tiny for many uses, as there is very little room to run cables, etc. For the price difference, it seems to be a better value:http://www.solar-electric.com/installation-parts-and-equipment/midnite/elenanddcdi/misobigbabox.htm
Here is the Link to the BigBaby box on the MN Site:http://www.midnitesolar.com/productPhoto.php?product_ID=122&productCatName=Small Breaker Boxes&productCat_ID=10&sortOrder=2&act=p
The exact boxes that you will want will depend upon weather you really need a Combiner, and a few other details of just what you need to do.