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What would say the issues and/or dangers here are?

Bill

I find this problem a lot and would appreciate some ammo for my arguments to replace such worn SE cable.

The "general public" consensus seems to be:

"Oh, it's just a ground wire..."

The local fire department had such an SE cable that had corroded to the point that only a few strands of the neutral were still connected. Ironic isn't it?

My guess is that corrosion is allowed to progress with the help of oxidation and UV light; eventualy to the point of a failed neutral before anyone does anything about it. (Then, of course, it's too late for some appliances..."why didn't you warn me?" they'll say...hmmmmm.)

The biggest problem I've had with cables like this is that they are no longer raintight. Water wicks down the cable & frequently starts the lugs in the meter corroding. I've also seen it continue past the meter & go down the cable to the service disconnect in the basement & rot out the lugs there.

If you need a code citation, try 300-12

Tom

What about possible shock hazards?

Bill

Yeah, I've seen lots of discos with rotting CB's even with the SE intact and the proper raintite connector used... This is of course when the disco is directly below the MB. I can easily see where this would aggravate the existing sealing problems.

Good Q Bill, what about the shock hazards?...
It's grounded but carrying lots of current...

these are everywhere ! the only thing missing is the semi-bare conductors out of the head, and the arc-welds from clacking together in the wind.

must be why that 'sunlight resistant' code was made [ 310-8(d)]

i point this sort of disaster-in-progress out when on service calls, etc. i usually ask them to ask any local sparky for a 2nd opinion.

As Tom pointed out, from what I see, one result of this condition is the entrance of water into the Meterpan which drips on the central Neutral lug an eventually rusts it away. If Panelboard is in Basement it gets water in it possibly damaging the Bus and/or Main Breaker.

To most this would seem to be a shock or fire hazard ... is it?

Bill

I would imagine fire would be the biggest concern if the neutral lug (or other connection of the neutral) allowed the infamous 240V series to smoke a few appliances.

Ground reference may be lost in places with poor soil, and poor grounding.

Someone in a panic to unplug said smoking appliances could be hurt by burn or electrocution.

Just MHO...

Any additional comments?

-Virgil ('66)

Its obvious that this service was installed a long time ago. And yes as the person that did the remodeling, siding, facier board trim. They most likely did not resecure the entrance cable.

This however is a serious problem. Not to mention Shock, as well as damaging equiment ect.

I think they should have some sort of inspection from time to time, especially in the older sections. I know that the inspection Department know that this type of thing is going on. They condem building for safty reasons ect.

I beleive a lot of the problems we have exisiting today is because of lack of concern.

Wayne,

Can someone explain the shock hazard to me. I don't doubt that there is one. I just don't understand the theory behind it. The grounded neutral is also bonded to the ground rod which is driven in the earth. Wouldn't it be the same as a person touching the bare #6 awg grounding electrode conductor which is installed from the service panelboard to the ground rod? There is no shock hazard with that example.

Frank (cinkerf)

Frank's right, the real hazard is the SE allowing water to flow into and corrode the terminations.
I did see one of these flow water into a Main breaker and start a fire in the panel..

Frank,

Sorry if this is a bit misleading. I think we're pretty much all in agreement here (also at MHE) that the main danger here is related to the entrance of water. I was trying to make a case for it being a shock hazard also under certain circumstances. This argument is undeniably very thin and would require extenuating circumstances. I was just fishing for scenarios where it might present a shock hazard to a Homeowner because that seems to be how they always perceive it. Every time I've mentioned that water could get in I hear "Can't We just tape it up?" Without the possibility of shoch hazard it may never get fixed. It would just start collecting layers of Duct Tape!


Bill

Bill,

I've seen the duct tape routine. I can understand your point.

Frank (cinkerf)

I've seen where the "noodles" were eaten almost all the way through, the surface area exposed helps speed up the corrosion.

In a 240V series circuit, the current wants to be the same throughout the circuit and therefore when Harry Homeowner panics and unplugs the sparking, smoking appliance from the wall by the #16 AWG cord with melting insulation, with reference to the neutral and ground lost, I see burn and/or electrocution to be very likely. I do understand that it takes just the right circumstances to achieve such a scenario.


[This message has been edited by sparky66wv (edited 05-12-2001).]

and then proceeds to fix the appliances with duct tape.....