Problem connecting Renogy MC4

[ZachO]

I feel like I read somewhere that Renogy MC4 connectors are slightly different dimensions than the typical MC4s. I'm connecting my Renogy panel to a cable hatch, to run the wires through my roof. The cable hatch came with wires, and the wires have the male MC4 on one wire, female on the other.

Renogy was the only brand I could find that wasn't selling packs of 5+, when I only needed one, so I bought them. Before I did any cutting of wires, I checked the Renogy MC4s to see if they'd "click" into the MC4s that came installed in the cable hatch. They did.

But now I've cut the wires, crimped one Renogy MC4 onto one wire...and it won't click onto the cable hatch connector. It will push most of the way in but not all the way over the rubber o-ring, or far enough to click into place.

Has anyone tried to connect Renogy MC4s to other brands? Did you have issues? I've only connected the negative side so far. I haven't crimped the positive side Renogy connector to the wire yet. That one still clicks into the cable hatch connector without problems. I'm curious if I somehow screwed up the crimping, and how that could affect the connector clicking together, or what's going on. I don't really see how it could cause a problem, no matter what I might have screwed up, but I don't know.

Any thoughts? You can see the connector on top, with the wire attached, won't go far enough to go over the red o-ring. Connector on the bottom, unattached to the panel wire, still clicks all the way without issues.

[gordon2]

Push harder.

And yes I have found different brands go together or come apart easier or harder than MC4s from the same company. I can do my Renogy MC4s by hand, even to undo them. But they are secure. With some others I need to tool to get them apart. And just last weekend while operating a radio transceiver off solar for about 16 hours I found one MC4 that could almost fall off a combiner adapter by itself. A slight tug pulled it apart.
Best to stick with one brand when you can, but with the cable hatch you might be stuck. If you cant find the same brand at the hatch then just push harder.. or maybe a very slight bit of silicone paste on the o-ring if that is where it is binding up... if it breaks then it was not meant to be

[ZachO]

Alright, I'll try force!

With some silicone lubricant. Good idea.

The cable hatch is Go Power, and I don't see any single MC4 connectors from them, only expansion kits with multiple connections.

[ZachO]

No go. I'm going to break stuff if I force it any harder.

I guess for now I'll hope it's more or less water-tight, and try to pick up another brand connector at some point and see if it fits any better.

[gordon2]

Well if you get really desperate you could break off ONE tab on the Go Power end.. then it should go on, and the other locking tab should hold it. Not the best solution Im sure.

[ZachO]

Or I guess I could replace the connectors that came installed on the hatch with Renogy connectors...but I'd worry that I'd mess up the rubber seal tugging on the wire to get enough length to work with. I ordered some non-Renogy connectors. Should be here in a week. We'll see how they work. Hopefully we don't get any torrential downpours in the meantime. I just spent a bunch of time yesterday scrubbing all the old adhesive, duct tape etc off my roof from the last installation and having a shower curtain taped over the leaky hatch...

[Air Doug]

I don't have Renogy brand but I did have some MC4 connectors from several different manufacturers, and a couple of them just wouldn't click in or only with a lot of force. I examined the clearances on the barbed clips, used calipers, and studied them some more. I was able to figure out that some of the clips were too wide and trimmed them just a bit. I can't remember if I sanded, Dremeled, or utility knifed, but just use what works. Now they insert and remove smoothly.

[ZachO]

Thanks Doug. Never thought I’d be a person who owned calipers, but it’s seeming more and more likely...What are you referring to as clips? The actual tab/ears, or another part of the plug?

Unfortunately I messed up the other wire connection so even if I got the one pictured to click, I’m without solar till I get the new connectors. Will need to be careful of my power use.

It was my first time using solar crimpers and it seemed like I got a good, tight connection, but the wire pulled out when I was working on things, and the plug stayed in the MC4 connector and wouldn’t come out without damage.

[SnowballCamper]

I switched to Anderson power pole connectors. I soldered them on... which can be a pain, but they work great.

[CASITA BANANA]

All my MC4s came from Renogy and I've found differences in fit. Some went together easy, some were extremely difficult. I imagine they might have come from different manufacturers with Renogy's label since I've built and added to my system over a period of time.

[Air Doug]

I agree with Alex and have switched to Anderson wherever I can.

[Huck]

My guess is the connector wasn't installed correctly (from experience).

[ZachO]

I'll have to look into Anderson. No experience with them.

Huck, by connector not being installed correctly, can you elaborate? You're talking about on my part, right? Being my first MC4 experience that's a very real possibility.

But, I watched videos on how to do it, and it's really not very complicated. I've crimped a lot of wires. You get the wire in the metal pole, crimp it, and insert the pole into the plastic housing until it more or less clicks in there and you can see the metal all the way into the plastic.

Can you point to where I may have messed up? I pulled it apart a couple times and when I'd put it back together, it always seemed fully seated, but even if not, I can't picture how that would keep the plastic parts from fully connecting. I'm completely willing to believe it's a possibility, I just can't picture it.

I assume that when I try a different brand connector, things will just work. But on the chance they don't, if it's something I'm doing wrong I'd like to figure that out. By the time the new connectors show up, I'm going to be pretty low on power and in a hurry to get things connected. I don't want to have the same issue come up due to user error.

[bobdobqb]

If I'm not mistaken, with the MC4 connectors if you happen to make the stripped end too long on the (I think) female connector it is possible to push the wire in too far so the male pin can't insert into the connection far enough. Could be?

[ZachO]

I'll check that out this evening.

Unfortunately that might mean I need a new connector on that side, too, unless I can un-crimp the end without damaging it. We'll see...

Too bad solar connectors are not available widely. Having to order online and wait is annoying! I'm used to running to the hardware store multiple times during a job That turns into a really long project when the hardware store is the internet and involves shipping.

[gordon2]

Shoulda bought the five-pack

[ZachO]

Hey now, I’ve beat myself up over that enough already!

I did order the 5-pack this time.

[Alex Adams]

Originally Posted by ZachO

Too bad solar connectors are not available widely. Having to order online and wait is annoying!

I assume you checked for local Solar companies in your area. Don't know where in Montana you are. You might also check with local RV places. These are becoming more common on RV's nowadays.

[ZachO]

Yeah, the closest solar company is a two hour drive, and while they probably have them, they don't advertise as a supply company, only a design and installation company. No RV store here; closest one is a one hour drive, but last time I was there I didn't see much selection of anything. There's a Camping World about two hours away, but they don't list them on their site. I haven't called. By the time I add up my time during the work week plus gas to drive four hours round trip plus however long I'm there, that's likely an entire work day missed and probably $50 in gas...I guess I'm willing to wait on shipping.

[Huck]

Originally Posted by ZachO

I'll have to look into Anderson. No experience with them.

Huck, by connector not being installed correctly, can you elaborate? You're talking about on my part, right? Being my first MC4 experience that's a very real possibility.

But, I watched videos on how to do it, and it's really not very complicated. I've crimped a lot of wires. You get the wire in the metal pole, crimp it, and insert the pole into the plastic housing until it more or less clicks in there and you can see the metal all the way into the plastic.

Can you point to where I may have messed up? I pulled it apart a couple times and when I'd put it back together, it always seemed fully seated, but even if not, I can't picture how that would keep the plastic parts from fully connecting. I'm completely willing to believe it's a possibility, I just can't picture it.

I assume that when I try a different brand connector, things will just work. But on the chance they don't, if it's something I'm doing wrong I'd like to figure that out. By the time the new connectors show up, I'm going to be pretty low on power and in a hurry to get things connected. I don't want to have the same issue come up due to user error.

It's been a while since I put any connectors on, but I think the problem I had was as bobdobqb mentioned, that the center conductor was cut a little too long so when pin was crimped on, it wouldn't snap into the connector. That then prevented the 2 mc4's from connecting.


You can also order just pins (Amazon).