EQUIPMENT GROUNDING CONDUCTOR FOR UNGROUNDED SYSTEM

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bobby ocampo

bobby ocampo

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What do you think is the purpose of Equipment Grounding conductor EGC) for UNGROUNDED SYSTEM? Is it exactly the same as the solidy grounded system?
 
In an ungrounded system a line to ground fault won’t clear. When you get a second line to ground fault then you have a line to line short circuit, which is why GF detection is required
 
tom baker said:
In an ungrounded system a line to ground fault won’t clear.
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What does the EGC accomplish for preventing electric shock if it will not clear the fault?
Will it cause electric shock if there is no EGC in an UNGROUNDED SYSTEM?
tom baker said:
When you get a second line to ground fault then you have a line to line short circuit, which is why GF detection is required
Click to expand...
Do you mean that in ungrounded system you need two line to ground fault before it will trip the OCPD?

On the first ground fault it will continue to function for UNGROUNDED SYSTEM?
 
What happens to a person touching a metal part of the panel in an UNGROUNDED SYSTEM if one of the current carrying conductor touched the panel and there is no EQUIPMENT GROUNDING CONDUCTOR?
 
bobby ocampo said:
What does the EGC accomplish for preventing electric shock if it will not clear the fault?
Will it cause electric shock if there is no EGC in an UNGROUNDED SYSTEM?

Do you mean that in ungrounded system you need two line to ground fault before it will trip the OCPD?

On the first ground fault it will continue to function for UNGROUNDED SYSTEM?
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Yes
Yes
Which is what I said
 
You can think thru the first question yourself.
HRG is not an ungrounded system. Do you understand how an HRG works?
 
bobby ocampo said:
What do you think is the purpose of Equipment Grounding conductor EGC) for UNGROUNDED SYSTEM?
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1. To allow fault detectors to work
2. To allow 2nd faults to clear.
3. To bond all non-current caring metal parts together to reduce touch potential from things like capacitive effects.
4. To connect all non-current caring metal parts to Earth to provide equi-potential during normal operation.
 
electrofelon said:
What does that have to do with Don's question?
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In an ungrounded system without a grounding conductor connected to the grounding electrode and connected to a metal enclosure of the service conductors you don't have a low impedance path to trip the breaker. In case of a phase to ground fault.
 
mtnelect said:
In an ungrounded system without a grounding conductor connected to the grounding electrode and connected to a metal enclosure of the service conductors you don't have a low impedance path to trip the breaker. In case of a phase to ground fault.
Click to expand...
The ungrounded system does not have bonding jumper, other than that is the same as a grounded system
 
tom baker said:
In an ungrounded system a line to ground fault won’t clear. When you get a second line to ground fault then you have a line to line short circuit, which is why GF detection is required
Click to expand...

Almost.

It’s line-ground-line. Usually the extra impedance won’t trip overcurrent protection.
 
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