How to wire a solar combiner box or pass through box

Learn how to wire a pass through box or a combiner box for your solar electric system.
⏱️Timestamps:
0:06 Intro
0:42 Reviewing pass-through and combiner boxes
2:35 Reviewing over current protection
3:13 Importance of electrical enclosures
4:14 Reviewing PV wires and safety
5:22 Cutting and stripping PV wire
5:38 Selecting an electrical enclosure
7:21 Installing strain reliefs and wiring
7:56 Fuse sizing and connections
9:08 Wire selection and transitions
10:16 Wiring the output through conduit
12:19 Equipment grounding
13:30 Other videos and resources
🗎 Publication:
Working on Solar Wiring and Fusing (EB-2023-0676)
go.umd.edu/EB-...
For more information, visit: go.umd.edu/Farm...

[@SetTheCurve]

This video really impressed me. Densely packed with practical information in a good time order and delivered in a clear way. Earned my subscription

[@Fester_]

Very groovy, thanks.

[@gajimafeet]

Gr8 explanations thank u so much

[@user-dr2pg8fk2i]

In understanding this was for display purposes, using bus bars like that is sketchy at best. There are much better devices for junctions.

[@TackleThat]

This! It seems like all 3 conductors are touching in the end.. man seems dangerous!

[@abauti9763]

Good instructional video! I noticed in other prebuilt combiner boxes that a surge protection is provided. When would you recommend to include an SPD in the combiner box?

[@LiveSounds11]

Would 4 strings going straight to the inverter need fuse protection in a pass thru box? Thanks keep rockin

[@ridemfast7625]

Can you explain to me what your pass through box is? Does the ground wire from the mounting rail go into the box and directly to the inverter? Did you use PVC or metal box? PVC conduit or EMT? If a metal box, did you attach it to the rail, run the rail ground wire into the box, ground it to the metal box, and run another ground wire from the box to the inverter?

[@ilyashick3178]

@@ridemfast7625 elecrical code is required to wire ground the equipment no matter metal or plastic boxes or inventer. In case of DIY local authority can tell what it is proper ground wire to get permission.

[@paulterry468]

There is some ambiguity on the DC side fusing and/or disconnect sizing in your videos that do not tie the two together very well. Question: If you have a non-fused disconnect in a combiner box, my understanding is that you size the fuses Isc*1.25 = Imax *1.25 for continuous current = Isc * 1.56 for the individual string fusing. The main disconnect then can be sized to match the Isc*1.25*1.25*# strings OR if the disconnect is 100% rated, it only needs to be sized Isc*1.25*# of strings. This could save $$$ in some cases. Is this the way NEC intended the sizing in a combined string fusing/combiner box? It seems to be the case with the caveat that the upstream fusing and wiring (i.e, path from combiner box to inverter) still needs to be sized the extra 1.25 even if using a 100% rated non-fused disconnect in the combine box

[@SUNofNY]

Some other videos say that wire nuts should not be used with PV wires... any thoughts on why they say this?

[@ratm183]

Does anyone know where to find the 2 hole liquid tight connector? I can find a 3 hole, 4 hole and the romex one, but none that have just 2 holes.

[@jussikankinen9409]

Does 230v fuse work 12v system

[@samfish6938]

wire nuts will burn at 100 amps