MC4 Connectors are incredibly common on solar panels. Generally, on most solar panels, there are two wires coming off the back of the panel and terminating with a male and female MC4 connector. In order to extend these wires to reach your charge controller, you’ll need to learn how to crimp MC4 connectors to make solar panel extension wires and this blog post will teach you how to do that.
What is an MC4 Connector?
An MC4 connector is a waterproof, UV resistant, quick-connect (and disconnect) connector that can generally handle a max of 20A and 600V.
How to Crimp an MC4 Connector (Video)
Tools Required for crimping MC4 Connectors
- MC4 Connectors: https://amzn.to/3dKS2pr
- Ratcheting Wire Crimper: https://amzn.to/3dVIdFw
- Wire Stripper: https://amzn.to/2WZu7wL
- Wire Cutter: https://amzn.to/2xHoqsu
- Red Solar Wire: https://amzn.to/2yl9MYk
- Black Solar Wire: https://amzn.to/2R4sk5H
Parts of an MC4 Connector
MC4 Connector – Positive vs negative
It’s important to understand that on opposite ends of a wire, there will be a male AND a female connector. Male on one end of the wire, female on the other end. Pay attention to which is which and don’t think “I always put male connectors on positive wires” because that would be incorrect. Think of this like: “I am needing to connect to this ‘male’ connector so I need to make a female mc4 connector here.” (It’s worth buying a few extra MC4 connectors because it’s highly likely you’ll mess this up a time or two.)
Darrell Rhodes
Friday 11th of September 2020
My only option is to have a 50-ft run from solar array (4-100 watt panels) to my charge controller. When I check for length of run it says 10AWG isn't big enough? So I won't have more than a 5% loss of voltage I need to run 6AWG? Is that correct? Please help...I need advice!!!!
Nate Yarbrough
Friday 11th of September 2020
Consider wiring your solar array in series-parallel OR 4x in series. Double-check, but this configuration looks appropriate to use 10 awg with the panels 50ft from the charge controller.
Roger Crandell
Saturday 22nd of August 2020
Do you spec a specific manufacturer of MC4 connectors? Do you have an opinion regarding which manufacturer makes the most reliable MC4 connector? What is your opinion regarding mixing (interconnecting) different manufacture's MC4 connectors in a single system?
Nate Yarbrough
Wednesday 9th of September 2020
Nope. Just any of them should work fine.
DON CLIFFORD
Thursday 21st of May 2020
Can I make a MC4 connection using 6awg wire?
Nate Yarbrough
Sunday 5th of July 2020
Nope. Most MC4 connectors are only good for 10 awg wire as they are only rated for 30 amps maximum. But if a solar panel array needs 6 AWG wire, something has gone wrong in the solar array design process as with an optimally designed solar array system, wire larger than 10 AWG is not needed.
Brad Holdridge
Thursday 7th of May 2020
Is there a difference in the type of wire used for solar panels... 1) what you reference in your blog (Temco 10 AWG Solar Panel Wire 100' Power Cable Black UL 4703 Copper Made in USA PV Gauge) versus 2) wire that I could get from Home Depot?
Nate Yarbrough
Thursday 7th of May 2020
Yeah, the stuff listed is rated for UV exposure and specifically for PV usage. The stuff at home depot isn't (unless it's PV specific, which I've never seen at home depot)