Neutral wire burning in surge protector

[KcBorne]

For the second time in about 2 months, the neutral wire leading from the OUT of my EMS-HW30C surge protector has burnt in half. I cut and cleaned the wires and now it's working fine, but i would like to understand why it is over heating. Here is a picture of the damage



The surge protector didn't give a reading for any problems.

[nbounder]

You've got a stinky situation here. Calling the tech at PI was a wise move. I am surprised they didn't send you a whole new unit right off the bat. I would call and pretty much DEMAND one, strictly for life protection. I pretty much go along with the posts above, but damn the reason, you have a life threatening situation and need to treat it as such. Get back on the phone and demand a replacement. After installation, monitor the temperature of the unit, and if it still gets hot, get an electrician in. Don't screw around here.

[swburbguy]

After you tighten the wire good and tight in the lug, give the wire a little wiggle. Then retighten it.

[MEXICOWANDERER]

Inside a screw type terminal block the block bore has to be shiny clean, as well as the copper strands that fit into it. A pass through connector bolt and nuts have to be SHINY clean, under the threads, flat washers sides, under the bolt head, the threads, everything. A 20 amp load applied to a semi bad connector can fire a wire in under 10-seconds, no matter how tight the screw or nut gets tightened. There is a hell of a difference between "no corrosion" and "shiny clean". To make things worse, an overheated connector or block can ANNEAL get too soft and cause problems later on. I would replace the burned wire, the connector fastener on BOTH sides or ends, and then check the outside wire and terminal with a magnifying glass. Not worth burning up at 3AM

[time2roll]

Consider some #10 or #8 solid wire in the connector and wirenut to the stranded.
Any copper that has been heated should be cut back until you have completely undamaged wire.

[KcBorne]

I just called progressive and spoke to the tech. He says if it happened 2 times in this short period of time, and it was fully tightened, that the problem is going to be something in the trailer it's self. They are sending me a new sensor and contact, but can anyone comment on what could possibly cause this on the trailer end aside from a loose connection?

and point taken danny thank you. I got a new one on the way. I take it that could be the cause of this 2nd failure. I'd still like to know what this man meant by the problem is on the trailer end.

[renoman69]

KcBorne wrote:
Thanks for the replies, I considered that, but I'm just wondering why this happened twice in a short period of time. The first time a friend who is a qualified electrician cleaned and reconnected the wire. He screwed it on very tight. I also live in this camper, so it's running 24/7. Would a high energy draw cause the neutral to over heat? The appliances i keep plugged in are the Fridge, Microwave, 2 lamps, 1 fan, flat screen TV, computer, computer speakers, toaster oven, toaster, and my wife's Hair straightener on top of the trailers AC unit. My surge protector currently reads 122v 3a 60h.

Get rid of the wife's hair straightener and you should be good to go.

[Denny___Jami]

The connection was never tight the first time causing it get hot and burn the wire, after that happens the lug on the terminal block is shot I don't care how hard you tighten it. That looks like a contactor so it will have to be replaced along with the wire.

Denny

[KJINTF]

As others have said it's a poor connection
Suggest you replace BOTH the wire and screw down terminal assembly

Never seen that specific failure mode in the few Surge Guards I repaired over the years

[teddyu]

Look at the lug set-screw threads in the picture. The neutral lead set-screw has about 2 threads exposed whereas the hot lead set-screw is recessed. I would speculate that the neutral lead set-screw is stripped internally. JM2¢...

[Acampingwewillg]

Looks pretty well chared on the lugs too.....Id replace what you can and coat all the wires with dielectric grease, then tighten them all down again.

[time2roll]

It needs a new connector but you could try to pigtail with some #8 solid.

I always worry about getting every strand under the clamp. I ended up using #8 stranded from the EMS to the panel. Solid #10 hits the input.

Can't find it by the foot anymore 😞

[jmanatee]

I agree, loose terminals cause heat. There are proper specs for tightening heavy gauge terminals. I use the VERY tight spec 🙂

I had a 125a breaker popping at my house caused buy a loose connection on 1/0 cable. Tightening it fixed the problem.

[KcBorne]

Any idea if progressive would replace the surge protector under the lifetime warranty? or would this type of damage some how void the warranty?

[KcBorne]

Thanks for the replies, I considered that, but I'm just wondering why this happened twice in a short period of time. The first time a friend who is a qualified electrician cleaned and reconnected the wire. He screwed it on very tight. I also live in this camper, so it's running 24/7. Would a high energy draw cause the neutral to over heat? The appliances i keep plugged in are the Fridge, Microwave, 2 lamps, 1 fan, flat screen TV, computer, computer speakers, toaster oven, toaster, and my wife's Hair straightener on top of the trailers AC unit. My surge protector currently reads 122v 3a 60h.