Circuit breaker box hisses

[clare]

And if it arcs again it will GUARANTEE you get a fire!!!!

[Ed Pawlowski]

I agree that it is best to inspect and replace burnt parts as needed. OTOH, if he can stop the arcing temporarily it is safer than allowing it to continue until he can do it right. If he wants to be completely safe, pull the meter until you can get an electrician.

[RealPerson]

By the way, you may also have a bad breaker causing that hum. Fix the Mains connection first, then watch and listen to the breaker feeding the laundry. If it does hum, replace it!

I will mention that when a motor starts, it draws a lot more amperage than when it's running. That's why you see that spark when it starts.

If you do shut off the power to repair that mains lug, check the other ones too (neutral included). And apply some Anti-Sieze to the screws so they are easier to move in the future. (Thats if they turn at all. That arcing could have welded that problem one in place, which means you have a bigger problem.

[clare]

A Ford by chance? My 1995 Mercury Mystique had the same issues

[clare]

Absolutely no way you need to (or even should) pull the meter. Just turn off the main breaker and no current can flow. No current means no arc. No heat. No problem.

[philo]

Since I worked on batteries and chargers the voltage was usually under

72 volts... but it was DC which is a whole different thing from AC.

My main point however was that if the OP heard hissing there was undoubtedly arcing and he really needs to call an electrician.

(the rest read but snipped for brevity)

[philo]

I knew better than to try and collect warranty on that one... yes it was Craftsman and I used the socket set the entire 38 years I was on the job.

The socket set was the only thing that lasted the whole time...and when it was time for me to turn in my tools, I kept it as a retirement present.

Obviously I replaced the parts shown in the photo and I took warranty on the ratchet a few times...but all other sockets went the distance.

[philo]

I worked a lot with connectors up to 350 amps and UL approved either soldering or crimping.

No one at my company had a problem with either method as long as done properly.

The important thing you did right was to cut back to good copper.

We usually crimped just because it was faster and no flames were needed to do so.

[philo]

Oh such memories. My first paid electrical repair job was my dad's '55 Chevy. Found a bad connector at the brake light. Cut the connector off...soldered and taped and got a buck from my dad. Think that was around 1962.

[philo]

You had a damn good job there. In the few years before I retired I saw a lot of companies getting the "IR checkup". Fix problems before they start...good idea.

[philo]

Worked on a lot high-powered transformers and if copper I could usually fix them by cutting back to clean copper and putting on a new lug.

Eventually I gave up on aluminum because no matter what I did, the connection would burn out again. I might have had better luck though if I used anti-oxidant paste. Too late now, I'm retired.

[philo]

Or determine which branh it's on and simply not use that side.

[Seymore4Head]

Hint: This is the main. The meter is the only way to turn off power here.

[Seymore4Head]

I forgot to add you do not have to turn the power off, but there is no reason not to.

[Ralph Mowery]

If the connection is subject ot viberartion, the crimp , if done correctly, is beter than soldering. The solder makes it into a solid wire and flexing will break it over time.

[clare]

A properly soldered connection is still better than an improperly crimped connection. Soldered connections should be re-enforced with heat shrink tupe beyond the solder-stiffened area of the wire.

[Ralph Mowery]

But the proper crimped connection is a lot berter than an improperly soldered connectiion.

You are defeating the purpose when not doing things the correct way.

[Texas Kingsnake]

Howdy folks,

I read all the excellent replies (thanks to all). Here's what I am going to do. I will put on my long linesman rubber gloves, place a thick rubber mat on the floor in front of the box and use a large insulated screwdriver to see if the screw (it's slotted, not hex-keyed) will turn and by how much.

I haven't been able to recreate the arcing since pushing the feed wire slightly right above the bus clamp. I will, on next trip to the box, look for discoloration of the wire in the clamp area and burn or sputter marks near the terminal. I will also try to measure the washing machine's start up current to see if it's abnormally high (if my clamp meter can register it - I believe it has a peak lock but am not sure - just got a new HF one to replace the Wavetek that had a terminal battery leak.)

I appreciate the concern for my life, Philo, and my wife is making sure my will is in order. I will wear goggles since I know a spasm of some sort could arc weld my screwdriver to the panel and throw molten metal into my eyes.

DPB - I'll try to take a close up picture of the wire where it enters the clamp but no guarantees. The last time I uploaded pictures no one could see them. I'll at least try to describe what I see now I know what I am looking for.

I'm upstairs now, but for some reason I thought the feed wire was tinned copper but it could easily be I was looking at aluminum wire and didn't realize it. The upgrade to the panel occurred in 1972 according to the labels, and IIRC that's when aluminum was still thought to be a good idea in residential wiring. I think you're right in that just pushing on the wire changed something because I cannot get the arc to occur DESPITE putting two space heaters running at 15A on the outlets served by the left side of the panel.

It's really just random chance we were both standing where we were when this happened - who knows how long it could have continued. I tried to assure my wife the reason that the circuits are in the metal box was to prevent an arcing connection from throwing sparks into the room. She's with Philo and thinks resetting the clocks and VCRs is worth the safety edge of working on a de-energized circuit. My opinon is "meh, you got to go sometime and getting eletrocuted is probably better than some ways of dying!!!"

I have a neighbor who is an electrician so I am going to consult with him tomorrow about what to do. If it's discolored and corroded at the entry to the clamp, I will consider replacing the entire feed wire from the meter to the panel since I think that's a relative small piece of what looks to be #6 wire - can't read the markings but am on my way downstairs with a camera with a macro lens. If all the feed wires are AL, I will consider replacing all three wires from the panel to the meter with new copper. If it happened on one wire, it's possible it could happen on the others.

And [e-mail], if the screw won't turn, I won't be spraying it with anything flammable while it's live. I feel comfortable trying to tighten the screw and take photos while it's live, but if it requires closer inspection, of course I will kill the power to the panel.

Thanks again for all the thoughtful replies. It might be a few days before you hear back from me if the worst comes to pass - well, if the very worst comes to pass (I die) you won't hear from me so I will try my best to let you know if I survive.

The worst shocks I've ever gotten were not from replacing breakers in a live panel but where I least expected it. I was changing a light bulb in a flooded basement when it popped in my hand and I was suddenly touching the naked filament wire. Or when I was working on a space heater that had stopped heating and thought I had unplugged it from the outlet but I had actually unplugged my DC variable power supply that was plugged in next to it. ZAPPPPPPP!

TKS

[clare]

But the "properly crimped connection" is not made with a $3.00 crimping tool and an insulated butt crimp connector consisting of a tinned copper tube and a hard plastic sleeve on it. A properly crimped connector requires a crimper with the correct size die for the connector, and a "calibrated" pressure, to ensure a "gas tite" connection - and an insulating sleeve that seals to the insulation, keeping moisture and other corrosive contamination away from the joint.

It is easier for a reasonably competent craftsman to make a decent soldered joint with tools at hand than to do a "proper" crimp without the specialized tools required.

That said, a "proper" crimped connection IS the preferred method of joining flexible conductors.

[Unquestionably Confused]

[snip]

Problem with that is that this is not a binary group. You have to upload the photo to a cloud source (Dropbox.com is free and easy to use) and then post a link (again easy with Dropbox) in your posting here. We just click on the link and ...