Splicing/Extending PV Cable

[Zeigh]

What do (responsible) professional solar electric installers use when having to splice together 12AWG cable on a rooftop installation?

I will need to extend some Enphase Q-Cable underneath a couple of solar panels and certainly know a variety of ways that it can be done. However, my goal is to make the splices as low profile as possible and without a bulky junction box. Surprisingly, there isn’t an Enphase accessory for this. There are various straight-thru products from third-party vendors, but either they are also too big and/or none that I have found so far that fit the demands of lasting for another 20 plus years in such a harsh environment.

Otherwise, I am planning to just get old school, twist/solder the wires, apply a dap of silicone on either end, then quickly enclose it all with a double layer of heat shrink tubing. Only a homeowner/installer would take the time to do this.


Peace,
Dr. Z.

[solarix]

One of the problems with the Enphase system is having to use their custom trunk cable. If you buy from them the exact cable you need, it easy - just plug and play. If you need to make alterations - not so much....

[Ampster]

What do (responsible) professional solar electric installers use when having to splice together 12AWG cable on a rooftop installation?

I will need to extend some Enphase Q-Cable underneath a couple of solar panels.....

Enphase sells connectors that allow you to make extension cables. My installation required three of those. They require the same crimping tools as MC4 connectors. I also made up one with connectors only on one end to transition through the Soladeck to the attic wiring which was just THHN in conduit.
My local supplier had the connectors but only sold the cable in 1000 foot spools. Fortunately the guys doing my roof work found someone who would sell the 30 feet we needed for this job. Several years earlier on another installation I found some cable on Ebay or Amazon. Caveat, I am not a professional installer but I do try to follow best practices.

[Zeigh]

Enphase sells connectors that allow you to make extension cables. My installation required three of those. They require the same crimping tools as MC4 connectors. I also made up one with connectors only on one end to transition to the attic wiring which was just THHN in conduit.

My apologies for not addressing the Enphase field wirable connector (Q-CONN-10M or Q-CONN-10F) in my original post. I was referring to a simple straight-thru design instead of a complicated male/female combination. The Enphase store website needs some work, as it gives all indication that a single male or female connector is $115! It always pays to shop around not only for price, but accuracy of information. I was able to locate a few vendors that offer versions of this connector at around $14. So, for four separate slices that will cost me $112, I could accomplish the same goal for just the cost of heat shrink tubing and solder.

I guess the important detail that I forgot about until now is possible warranty coverage and "authorized equipment". NEC also probably requires a waterproof junction box unless there is an approved product specifically for solar electric use. More research ahead.


Peace,
Dr. Z.

[Ampster]

The $115 price is for a pack of ten. I used them because it made it simpler for the guys working on the roof. In my case I could make up the cables on the ground and keep them on the roof working on the system. I also wanted the flexibility the extension cables offered but soldered shrink connections would work fine. I do not think there are any warranty issues. I have an RMA pending for one inverter and Enphase did not ask about the string connections.

[Zeigh]

I have an RMA pending for one inverter and Enphase did not ask about the string connections.

Sorry that I am sidestepping the topic, but may I ask how you discovered a microinverter problem? I basically check on my system through the Enlighten portal every other day and have a high alert parameter for notification emails, but really just leave it up to Enphase to tell me if there is an issue or not. Of course I will eyeball the numbers, but nothing in depth. Like my OCD needs another thing to get all geeky with...


Peace,
Dr. Z.

[Ampster]

........may I ask how you discovered a microinverter problem? ......

It is a new system and the error showed up on the system status on the Envoy,

[Mike90250]

Use properly rated ( outdoors ) crimp and heat shrink splices. This may need to happen inside a weatherproof box.

Do not solder. Proper crimps are gas tight and won't corrode. Solder adds flux byproducts, wicking issues, and the uncomfortable melting if there is an overload..