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.)
JJ
Tuesday 28th of September 2021
I have a 200 watt panel. I need a 50 foot long run. Is 10 awg good? According to certain calculations I need 8 awg but I don’t see it.
Marion Floyd
Tuesday 3rd of August 2021
My {4} Rich Solar 100watt kickstand panels have 12 gauge anderson plugs. The panel wires neg and pos wires are molded together. Can I hook them up to a {rv} pv wall/roof inlet that is prewired with 10 gauge mc4 ? Should I cut the anderson plugs off and split the molded wires separately and install mc4 connectors so I can series/parallel my 4 panels? Do you have any diagrams I could use to hook up my 4 panels and stay under 12 amps for a Bluetti ac200p or possibly a 6x100 watt array if I buy 2 more panels? Please steer me to a good tutorial on building panel/mc4 custom making array wiring. Any help would be appreciated. mgfloyd@zoomtown.com
Shari Johns
Tuesday 29th of June 2021
Why do all the MC4 connectors have red rubber bands? This makes me think they are all positive and I know that can't be correct.
Mike
Saturday 19th of June 2021
I wanted to thread the cables from my panel through a gland, but the MC4 connectors came preinstalled. Is there some way to back the crimped cables out of the connectors so I can thread them, or am I stuck redoing new crimps? I really want the connections indoors if I can.
ning
Saturday 22nd of May 2021
I brought your figure before. There are 6 PV connectors, three males and three females on MPPT 150/85-MC4 solar charge controller. What is each one? Which do I need to connect positive and negative to ? Thanks
Nate Yarbrough
Sunday 23rd of May 2021
There is a + and a - in front of the MC4 connectors that tells you which is which.