On another thread:
https://www.electrical-contractor.net/ubb/Forum2/HTML/002236.html the idea was brought up to have a "bolted short"
intentionally placed while working on equipment to protect against someone energizing the circuit while work was in progress. (Primarily to protect against those Darwin candidates who don't understand lockout/tagout.)
While the logic may seem sound {any inadvertant energization would be shunted to ground or cleared by the OCP device} I feel the risks aren't worth it.
For example:
Possible explosive failure or dangerous heating of the device(s) used to act as the bolted fault;
Possible violent failure of the circuit breaker/disconnect/fuse while closing in on the fault;
Additional damage to equipment/feeders by the above or failure of the OCP device to open;
Impression of dangerous voltages/currents on metal enclosures/parts if the impedance of the grounding path is not adequate;
The possibilty of workers forgetting to remove the bolted fault upon completion of work.
It would be hard to imagine many work situations where one couldn't tape up/cover/isolate the equipment being worked on. And testing with a volt-tic or meter
as many times as needed for safety during performance of the task would be a better option IMHO.
As I'd mentioned in the referenced thread, I'm not talking about POCO work, where grounding rigs are commonly used. All the POCO guys I've talked to say the grounding rig must also be placed out of the work area but as close as practical (on overhead work, usually within one span.) Mainly, to keep it out of the way, but also in case the line is heated up and the rig blows it'll be out of harm's way.
What do you folks think?
