discoloring Insulation in panel

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Bsquared

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Hi All,

I'm in process of upgrading my old panel it is a 12x12x8 30A two 5500W element system. I've been running it for about four years and have noticed that it generates a lot of heat, probably getting up to 120-125 in side the box during a brew day. Im looking to add some outlets for a third pump and a CIP pump, so I got a larger panel 20x15x8 and added an external heat sink to give me more room and mitigate heat.

One think I have noticed is that the insulation on my hot leg wires coming in are starting to discoloring. They are 10 gauge, but Im wondering if it would be better to use 8 gauge, as these are the legs that feed everything in the panel.

I did have a problem a while back where the lock down screws on some of the outlets and plugs had loosened and were generating heat, and one plug melted. so this could be from this problem. I have since been periodically checking my connections and have tined all those connections to resolve this.
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the wire size is fine... two factors are likely working against you though, is the wire rated for AC current or is the insulation for DC automotive use?

2} double check the connections at the ends of the wire... a poor/ weak connection will cause more resistance and the insulation to melt... if your ambitious it would be better to solder on the connector at the end or the wire at the contractor end.

didnt you also have one ofyour outlet connections melt a while back from the connections being poorly secured? I thought I remembered this in another thread about 6 -8 months ago?
 
the wire size is fine... two factors are likely working against you though, is the wire rated for AC current or is the insulation for DC automotive use?

2} double check the connections at the ends of the wire... a poor/ weak connection will cause more resistance and the insulation to melt... if your ambitious it would be better to solder on the connector at the end or the wire at the contractor end.

didnt you also have one ofyour outlet connections melt a while back from the connections being poorly secured? I thought I remembered this in another thread about 6 -8 months ago?

Yes, I had a plug melt down about that long ago, I went through the panel and tined all the connecters and re-tightened all the connections. have not had an issue sense.

This is AC rated wiring, Im suspecting this is a result of the connection issue. Im hoping that tinning the ends of the wires and periodically checking the connections will help resolve this.
 
I know I sound like an ass, but these issues your having are scaring me. You need to reevaluate your wiring practice. If you can get rid of those crimp ons or get the proper crimpers that apply the correct amount of force. If your using these

View attachment ImageUploadedByHome Brew1443394806.303265.jpg

Throw them in the trash and get a real pair of crimpers.

Until then keep a fire extinguisher close by when your using your panel.

Good luck
 
That wire has been overheated. This is a real safety concern and you should not proceed without figuring out what is happening and a remedy.

It does look like more discoloration/burning at the distal end rather than at the receptacle. It is likely the crimp as TMD pointed out. You should also ensure you are matching your wiring to your load (and check it with an ammeter), though I doubt this is what's going on.

Seriously... this needs be fixed before someone gets hurt. And we dont want our HB brethren hurt!

-BD
 
I have a hard time telling where that's going into, but looks like just a spade. Any chance of upping it to a ring and making sure it's torqued down nicely? Looks like a contactor, can you not just sandwich the bare wire into the screw port?
 
I know I sound like an ass, but these issues your having are scaring me. You need to reevaluate your wiring practice. If you can get rid of those crimp ons or get the proper crimpers that apply the correct amount of force. If your using these

View attachment 306033

Throw them in the trash and get a real pair of crimpers.

Until then keep a fire extinguisher close by when your using your panel.

Good luck
Thats what I used to crimp.
And yes there is an extinguisher by my panel.

I think what I am experiencing is thermal expansion is causing the screws for the inlet plug to loosen and generate heat. I think I resolved this with tinning the wires and tightening the connections.

Ive brewed many batches on this system with only the one incident, where the GFCI tripped. I was able to re-wire and finish the brew. so don't worry I have all the safety systems in place. :rockin:
 
Thats what I used to crimp.

And yes there is an extinguisher by my panel.



I think what I am experiencing is thermal expansion is causing the screws for the inlet plug to loosen and generate heat. I think I resolved this with tinning the wires and tightening the connections.



Ive brewed many batches on this system with only the one incident, where the GFCI tripped. I was able to re-wire and finish the brew. so don't worry I have all the safety systems in place. :rockin:


The problem is it isn't working. This failure mode doesn't happen unless there are errors in the wiring. Please for the love of God, if your going to use those crimp on connectors, use a name brand like Amp, and get a crimper that can apply the correct amount of force to properly crimp the terminal. This is NOT an area to save money on.
 
That wire has been overheated. This is a real safety concern and you should not proceed without figuring out what is happening and a remedy.

It does look like more discoloration/burning at the distal end rather than at the receptacle. It is likely the crimp as TMD pointed out. You should also ensure you are matching your wiring to your load (and check it with an ammeter), though I doubt this is what's going on.

Seriously... this needs be fixed before someone gets hurt. And we dont want our HB brethren hurt!

-BD

I agree with BD that heat, evidenced by insulation discoloration, seems to be generated at the crimp, or connection where wire junctions with relay. It is difficult to see what is going on at the connection? Lack of screw pressure, bad crimp are possibilities.
 
I always buy the cheap harbor frieght crimp connectors and never have this issue so I'm not sure I agree about the cost of the connectors being the issue... if I had to guess Id say it just wasnt crimped tight enough... The OP has already mentioned he was going to solder it to address this and make all this a moot point so....We are beating a dead horse here IMO.
 
i believe the issue is using a cheap crimper, not necessarily cheap crimp connectors. cheap connectors crimped properly are way better than top-of-the-line connectors that have been attached with a cheapo crimper.

not to say one can't make successful crimps with cheap crimpers but it is certainly more difficult than using good crimpers.
 
Yeah, $20 on a ratcheting crimper (or soldering I guess) is a good use of money when building these panels.

To me it still looks like the spade might not be making the best contact at the terminal? Can't really tell what's going on there but for the big power mains **** using spades.
 
From the picture it doesn't appear that the plastic skirt part of the ring terminal is crimped tight enough or that enough pressure was applied. I am no electrician by any means, not even close, but I can tell you when I was wiring up the elements in my enclosures the other day, I used a ratcheting crimper on the 10/3 wire and I used yellow 10 gauge ring terminals. Let me tell you it took a great deal of pressure squeezing the crimper handles together in order for the tool to make the crimp and then release. It put two nice deep crimps in the terminal skirt. If I didn't have a ratcheting crimper I would not have known just how hard to squeeze the handles to make the proper crimp and I probably would not have squeezed the handles as hard as the ratcheting crimper did, because of the lack of experience on my part. I'm glad I had the right tool for the job. Just saying.........

John
 
x2 on the ratcheting crimper. I bought these a few years back and have not had any electrical problems with connections. Please use a ratcheting crimper. You probably wouldn't torque down engine bolts without a torque wrench and it's the same idea with crimped connectors.

http://www.amazon.com/dp/B000NI3EMK/?tag=skimlinks_replacement-20
 
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Cool ratcheting crimper , That sounds like a good thing to get for the new build. I was never happy with the crimper I was using, but did not know how to test the connection, other than giving it a slight tug. Guess I look in to that.

So what Im getting here, is 10 gauge AC rated wire should be fine to handle the input power, Tinning ends and a ratcheting crimper will help with securing the terminals.
 
Cool ratcheting crimper , That sounds like a good thing to get for the new build. I was never happy with the crimper I was using, but did not know how to test the connection, other than giving it a slight tug. Guess I look in to that.

So what Im getting here, is 10 gauge AC rated wire should be fine to handle the input power, Tinning ends and a ratcheting crimper will help with securing the terminals.

I don't think you are supposed to tin the wire ends prior to crimping. It would interfere with the proper compression of the wire in the crimp. If you want to solder, do it after the crimp.

Brew on :mug:
 
I don't think you are supposed to tin the wire ends prior to crimping. It would interfere with the proper compression of the wire in the crimp. If you want to solder, do it after the crimp.

Brew on :mug:


That makes sense, but I was referring to tinning the wires that go in to the Outlets and terminal blocks. The post and screw connections will just get crimps. Just bought the ratcheting crimper, and am looking a heat shrink terminals too.

Im hopeful I can get this re-built in a week or so, want to get back brewing. Looking forward to firing up the new kettles.
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That makes sense, but I was referring to tinning the wires that go in to the Outlets and terminal blocks. The post and screw connections will just get crimps. Just bought the ratcheting crimper, and am looking a heat shrink terminals too.

Im hopeful I can get this re-built in a week or so, want to get back brewing. Looking forward to firing up the new kettles.
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Why would you tin any of the wires in a build? I dont see why you would even ever want to tin the wires going into the socket...or a terminal block? You want the compression of the wire for maximum hold and contact area...
 
As others have said, get a real crimper, use the correct size ring lugs, no spades. Try not to put more than one per screw terminal. Also make sure your contractors coils are correct voltage and type for what your using. Hopefully your not getting chatter. If you used cheap contractors, look at the contacts and make sure they are still in good shape. Also if possible try not to pull a load across them before they are energized. This will prevent unnecessary arcing.
 
So I took apart the old panel and started re wiring the new panel. I bought a pair of ratcheting crimper and a wire striper and am paying close attention to the striping of the wires to there proper lengths and trimming them neatly, so there are no stray wires or un-even cuts. as well as the proper lengths for each connection. As well I'm using terminal blocks, wire race tracks and din rails.

So far its coming together nicely. Hope fully will have it finished in the next few weeks if I can get time.
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Nice! You may want to get some split loom tubbing or wire wrap to protect the wires from the door to the wire tray, last thing you want is a wire smashed in the hinge or caught on a relay that pops out when you open the door.
 
I did have a problem a while back where the lock down screws on some of the outlets and plugs had loosened and were generating heat, and one plug melted. so this could be from this problem.
Definitely a (if not "the") problem.

Heat is created when current flows through an area that is too small to handle the amount of current. This can happen:

(a) with a loose connection where only a few strands are making contact because the wire is not properly tightened/fastened, and/or
(b) a wire that is too small to handle the current is used, and/or
(c) when a properly sized wire is used but some of the copper strands were cut/trimmed to get it to fit (this should never be done)

All of these cases effectively reduce the contact area meaning that more current flows through a smaller area which in turns creates more heat which can melt the insulation on wires and damage nearby components.

Old(er) thread, but I figured I'd chime in.

Kal
 
if folks really want to be doing it right, they need to get a torque screwdriver to ensure the connections are the proper tightness. manufacturers publish torque requirements for their terminals so short of having the actual tool, it is a bit of a guess if the connection is made properly. for most applications, making it 'tight' is good enough but it is possible to overtorque and create a weak connection as well. for the size conductors and terminals encountered in a brew panel, this typically isn't an issue but something to keep in mind...
 
Thanks Kal, after disassembling my panel, a could tell it was "a)" that was the problem at the inlet. I could see where the un even cut of the wires was causing an arc and damaging the connection. So I'm making sure I have square cuts and the proper length strip with this build. I'll look in to a torquing screw driver too.
 

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