Service cable protection

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Electriman

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I had a short after the meter and before the service disconnect and the short happened between the phase and the electrical panel enclosure via a screw driver. The short was strong since it damaged the screw driver. But I have a concern about the service cable. I have the voltage in the panel but I am wondering how the service cable is protected. Any idea? How do I know they are safe?
 
Service conductors are not protected against overcurrent or faults. In some cases, a utility device upstream of the service transformer might open, but that is not always the case. If the screwdriver had been stuck in place, the fault might not clear at all, with the result of damage or even a fire.

Why is this acceptable, you ask? We permit this risk because we take great pains to prevent it from happening. That sometimes includes limiting the length of the conductors, and always includes providing physical protection for the conductors. The hand that held the screwdriver bypassed these safety measures.
 
charlie b said:
Service conductors are not protected against overcurrent or faults. In some cases, a utility device upstream of the service transformer might open, but that is not always the case. If the screwdriver had been stuck in place, the fault might not clear at all, with the result of damage or even a fire.

Why is this acceptable, you ask? We permit this risk because we take great pains to prevent it from happening. That sometimes includes limiting the length of the conductors, and always includes providing physical protection for the conductors. The hand that held the screwdriver bypassed these safety measures.
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Thanks. This was a pure accident there was no intention. The conductor between the meter and service disconnect was tapped for EV charger. But the tap was loosed and burned the insulation of the #6 wire. This means that it gets too hot to burn the insulation. So I am guessing the conductor between meter and main disconnect is not sized to handle the additional load for EV charger.
 
Electriman said:
Thanks. This was a pure accident there was no intention. The conductor between the meter and service disconnect was tapped for EV charger. But the tap was loosed and burned the insulation of the #6 wire. This means that it gets too hot to burn the insulation. So I am guessing the conductor between meter and main disconnect is not sized to handle the additional load for EV charger.
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'sounds like the #6 tap for the EV charger is not protected against overcurrent nor faults, either.
 
Electriman said:
Thanks. This was a pure accident there was no intention. The conductor between the meter and service disconnect was tapped for EV charger. But the tap was loosed and burned the insulation of the #6 wire. This means that it gets too hot to burn the insulation. So I am guessing the conductor between meter and main disconnect is not sized to handle the additional load for EV charger.
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Not necessarily, but not a definite yes either. The loose connection was very likely the main factor in your overheating incident.
 
Electriman said:
I had a short after the meter and before the service disconnect and the short happened between the phase and the electrical panel enclosure via a screw driver. The short was strong since it damaged the screw driver. But I have a concern about the service cable. I have the voltage in the panel but I am wondering how the service cable is protected. Any idea? How do I know they are safe?
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What justified that energize work? I can't imagine a way to justify energized work for this application.
 
when I was an apprentice I drilled into the very short section of SE cable( the Rim & floor joist area)from the meter to the panel with an auger bit and instantly started a fire. Luckily my employer had fire extinguisher.
 
If it's an emergency I might notify them and pull it myself or they will send a field person out immediately and be on call to reconnect when I'm finished.
However, I wouldn't think EV chargers are emergency connections?

I do understand the frustration of dealing with some POCO's and after waiting past a scheduled time I would probably just pull the meter.
 
Electriman said:
Because they never come. Honestly, when there is an emergency do you call POCO and let your customer to be without power for a couple days at least?
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There should be emergency field people on call 24/7 (if not, the regulators are doing a bad job). A couple of years ago there was a fire at my next door neighbors. The Fire Dep't call the POCO and they had a lineman out to cut the power at the pole pretty quickly (1/2 hour or so). They pulled my meter as a precaution since my Service Entrance wasn't far away from them. When the fire was out they were called again to re-install my meter; it took them about an hour or so. And this was a 5 AM.
 
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