Has anyone had any issues with terminal connectors coming loose?

[poot_traveller]

There is a lot of vibration in a vehicle and a lot of bumps in the road, I imagine solar panel systems must get banged around a bit.  I was wondering if anyone had any problems with any terminal connectors/nuts/screws, etc coming loose anywhere on their solar panel system?

 

[maki2]

If you try to do your crimps with one of those cheap hand crimpers from a hardware or automotive store then you very likely will have problems.

But the crimps won't come loose if you use good quality tools to make them and get the pressure set right.
A worthwhile investment are ratcheting crimpers.

They make ratcheting crimping tools for doing the connections for Solar and for the pin ends that fit into Anderson connectors as well as for the standard crimp on wire connects such as butt splices and ring terminals.

So invest in the tools the pros use and you can do professional quality work. Youtube has all the instructional videos on how to use those tools to get excellent result.

As far as nuts coming loose you can use thread locker chemicals and another choice is Nylock nuts. But when you use stainless steel fasteners and nuts then you should also apply anti-sieze to the thread before putting on the nut. Otherwise you might not be able to remove the nut because of "galling" On stainless steel Nylock nuts will induce galling.

You should read this article about what galling means. Everyone who does a build should know about this basic fact of using nuts and bolts but few beginner DIY users are familiar with it. https://www.boltdepot.com/fastener-information/materials-and-grades/thread-galling.aspx

 

[poot_traveller]

Thanks for the tips. I crimped and soldered the ring terminals. I'll look into getting some threadlocker and Nylock nuts.

I'll be honest, I'd rather the nuts stick on permanently to the thread due to galling, than have the nuts come loose.

 

[Lowdesertpatrol]

Yeah of course. Thread lock helps and for grub screws such as fuse blocks try these.

 

[MrNoodly]

Lots of bumpy roads. No special measures taken with connectors. No problems in six+ years.

(There's probably a reason there aren't a pile of threads here about loose solar connections.)

 

[1shemp]

I just use wire nuts so I can remove the panels from the van in the fall.No problem with them coming loose.

 

[highdesertranger]

pinch type connections, where you have a set screw that pinches down on the wire are well known for coming loose. these are common in car audio components and lesser quality stuff. they even come loose in houses that don't move down the road. same with wire nuts. use the correct terminal for the job. a good place to learn is from marine codes. much stricter than for vehicles. highdesertranger

 

[Doubleone]

If you use quick connectors under the hood or outside in the weather, be sure to use some dielectric grease to keep the terminals from corroding.  Not wanting to start a storm here (some people have very strong views on this) but crimp, solder, and shrinkwrap has been dead reliable for me in the race cars and off-road race trucks. Metal fatigue from vibration is a big deal in racing, so much so that we even have to prep the radios by potting the electrical components with hot glue.  When wiring, leave some extra long shrink wrap at the terminals for vibration and to act as a strain relief.  Consider leaving drip loops in any through wall connections so water doesn't migrate inside your rig.  When using ring terminals I dab a blob of silicone over the top of the screw head or nut to keep them from backing off.  The silicone can be removed easily with a pick or screwdriver when it's time to come off.

 

[maki2]

Thanks for the tips.  I crimped and soldered the ring terminals.  I'll look into getting some threadlocker and Nylock nuts.

I'll be honest, I'd rather the nuts stick on permanently to the thread due to galling, than have the nuts come loose.

You should not solder the ring terminals or other terminals. The stranded wires are fine gauge. If you apply solder then the wires can't flex properly. So the solder can lead to work hardening of those wires and that means they can break through repeated flexing. The proper way to do it for vehicles is to crimp but not solder and crimp. This is one area where belt and suspenders assumptions can lead to early failure rather than being a safety backup just in case.

 

[maki2]

I'll be honest, I'd rather the nuts stick on permanently to the thread due to galling, than have the nuts come loose.

The situation is this. If they gall there will be hell to pay getting them off should you need to modify or replace things. The thread locker will be more than sufficient. I can see that you like belt and suspenders approaches and while that works for some things it is not always appropriate. 

Very few van builds stay the same over time. You need to be able to make modifications later on without having to cuss at yourself when you can't undo what you have done. The goal is to be safe but not to try to make it harder on yourself to make repairs and modifications. Use thread locker, use anti sieze. That is how the pros do it. You have been given the information for the right way to approach these things. Just do it like the pros do it.

 

[poot_traveller]

Yeah of course. Thread lock helps and for grub screws such as fuse blocks try these.

Hmmm those are interesting. I'll look into these. Thanks

 

[poot_traveller]

Lots of bumpy roads. No special measures taken with connectors. No problems in six+ years.

(There's probably a reason there aren't a pile of threads here about loose solar connections.)

That gives me peace of mind. It's been my main concern lately. Thanks

 

[poot_traveller]

pinch type connections, where you have a set screw that pinches down on the wire are well known for coming loose. these are common in car audio components and lesser quality stuff. they even come loose in houses that don't move down the road. same with wire nuts. use the correct terminal for the job. a good place to learn is from marine codes. much stricter than for vehicles. highdesertranger

Ah yes, luckily I didn't use any pinch type connectors. One of the few things I did get right.

 

[poot_traveller]

If you use quick connectors under the hood or outside in the weather, be sure to use some dielectric grease to keep the terminals from corroding.  Not wanting to start a storm here (some people have very strong views on this) but crimp, solder, and shrinkwrap has been dead reliable for me in the race cars and off-road race trucks. Metal fatigue from vibration is a big deal in racing, so much so that we even have to prep the radios by potting the electrical components with hot glue.  When wiring, leave some extra long shrink wrap at the terminals for vibration and to act as a strain relief.  Consider leaving drip loops in any through wall connections so water doesn't migrate inside your rig.  When using ring terminals I dab a blob of silicone over the top of the screw head or nut to keep them from backing off.  The silicone can be removed easily with a pick or screwdriver when it's time to come off.

Dielectric grease will be required, I have grounding connectors on the chassis.

That's a good tip about the silicone, unorthodox, but good. I'm going to use your silicone trick.

Thanks

 

[poot_traveller]

You should not solder the ring terminals or other terminals. The stranded wires are fine gauge. If you apply solder then the wires can't flex properly. So the solder can lead to work hardening of those wires and that means they can break through repeated flexing. The proper way to do it for vehicles is to crimp but not solder and crimp. This is one area where belt and suspenders assumptions can lead to early failure rather than being a safety backup just in case.

The soldered ring terminals look good, I just checked. There won't be any flexing going on. I'm more worried about the nuts backing off.

 

[poot_traveller]

The situation is this. If they gall there will be hell to pay getting them off should you need to modify or replace things. The thread locker will be more than sufficient. I can see that you like belt and suspenders approaches and while that works for some things it is not always appropriate. 

Very few van builds stay the same over time. You need to be able to make modifications later on without having to cuss at yourself when you can't undo what you have done. The goal is to be safe but not to try to make it harder on yourself to make repairs and modifications. Use thread locker, use anti sieze. That is how the pros do it. You have been given the information for the right way to approach these things. Just do it like the pros do it.

I'm really not keen to unscrew everything, especially not the inverter, I've got it to a point where everything is holding steady, before that a few connections were loose and no matter how tight I did these up they remained loose and I could move the cables around. But not anymore.

I'll buy some thread locker and anti-sieze just in case, and pull on the cables once in a while to make sure the nuts and screws haven't come loose.

It will be just my luck if I start messing with the connections, everything will come loose and stay loose like before.
I'm testing the solar panel system in 2 days and I don't want to be left scrambling trying to fix loose connectors that refuse to tighten up.

 

[B and C]

Connections that won't tighten up sounds like either stripped threads or the wire is too small for the connection.

 

[poot_traveller]

Connections that won't tighten up sounds like either stripped threads or the wire is too small for the connection.

It was actually the nuts that wouldn't screw up tight on the inverter but it's all sorted now.

 

[Doubleone]

Dielectric grease will be required, I have grounding connectors on the chassis.

That's a good tip about the silicone, unorthodox, but good.  I'm going to use your silicone trick.

Thanks

Not so unorthodox in desert racing...  I learned that trick from a pro trophy truck team that races in Baja.  Another product I use... instead of Blue Loctite is Tru-Blue pipe sealant.  I use it for both for pipe threads and threaded bolts exposed to high vibration. It's cheaper, comes in a big tube, has multiple uses, keeps stuff in place as good as Blue Loctite but the Tru-Blue stays pliable, doesn't dry out, and acts as an anti-sieze.  It's a mainstay in my kit.  I do occasionally use Red Loctite for certain stuff not meant to ever come off, but Red can sometimes pull threads from aluminum so caveat emptor...

 

[LoveCareThinkDo]

YES! I had a hell of a time getting the cheap crimp-on-lugs to even stay on the wires in the first place. The metal that the crimp-on-lugs are made of these days are just too thin and soft. So, no matter how hard I squeezed my crimpers the wires would just slip right out. It took about five tries per connector to get things to work right.

I need to find a really good brand of crimp-on-lugs that are readily available at either auto-parts or RV stores.