ground-fault protection of equipment

[binwork91]

480/277 Y system.
If breaker is 1600A frame, but with 800A sensor.
1. does it need to have ground-fault protection setting? the highest continuous current trip setting is 800A with 800A sensor.
2. with LSIG 800A sensor, do I have to set the ground fault setting?

 

[infinity]

Is this for a feeder? 230.95 for services has a slightly different requirement.

215.10 Ground-Fault Protection of Equipment.
Each feeder disconnect rated 1000 amperes or more and installed on solidly grounded wye electrical systems of more than 150 volts to ground, but not exceeding 600 volts phase-to-phase, shall be provided with ground-fault protection of equipment in accordance with 230.95.

230.95 Ground-Fault Protection of Equipment.
Ground-fault protection of equipment shall be provided for solidly grounded wye electric services of more than 150 volts to ground but not exceeding 1000 volts phase-to-phase for each service disconnect rated 1000 amperes or more. The grounded conductor for the solidly grounded wye system shall be connected directly to ground through a grounding electrode system, as specified in 250.50, without inserting any resistor or impedance device. The rating of the service disconnect shall be considered to be the rating of the largest fuse that can be installed or the highest continuous current trip setting for which the actual overcurrent device installed in a circuit breaker is rated or can be adjusted. Exception: The ground-fault protection provisions of this section shall not apply to a service disconnect for a continuous industrial process where a nonorderly shutdown will introduce additional or increased hazards.

 

[binwork91]

Is this for a feeder? 230.95 for services has a slightly different requirement.

It is service switch, and same breaker on generator.
But for 480V, they are same requirement.
feeder: not exceeding 600V.
Service disconnect: not exceeding 1000V.

 

[infinity]

It is service switch, and same breaker on generator.
But for 480V, they are same requirement.
feeder: not exceeding 600V.
Service disconnect: not exceeding 1000V.

Since your at 480 volts you can use the provisions for adjustable trip in 230.95 if applicable.

 

[binwork91]

Since your at 480 volts you can use the provisions for adjustable trip in 230.95 if applicable.

Can you answer my following question, I just want to make sure i am not misunderstand it.
1. if my service breaker is 1600A/F 800A sensor, 480V/277 Y system, then I don't need to ground fault if exception comply. correct?
2. if my service breaker is 1600A/F 800A sensor, 480V/277 Y system, if exception does not comply, i don't need ground fault, because highest continuous current trip setting is 800A, is less than 1000A. correct?
3. if my generator main breaker is 1600A/F 800A sensor, 480V/277 Y system, i don't need ground fault, because highest continuous current trip setting is 800A, is less than 1000A. correct?
4. if my sensor is 800A LSIG, can I not set up G setting, because it is not required.

 

[don_resqcapt19]

The requirement is triggered by the rating of the breaker overcurrent device installed in the breaker. If that rating is less than 1000 amps ground fault protection is not required.

230.95 ... The rating of the service disconnect shall be considered to be the rating of the largest fuse that can be installed or the highest continuous current trip setting for which the actual overcurrent device installed in a circuit breaker is rated or can be adjusted.

For your #4 you can set up ground fault protection anywhere you want. The code does not prohibit that.

 

[binwork91]

The requirement is triggered by the rating of the breaker overcurrent device installed in the breaker. If that rating is less than 1000 amps ground fault protection is not required.

A 1600A frame breaker with an 800A sensor can only be adjusted to 800A. However, the sensor can be easily changed to 1600A. Does this mean that with a 1600A frame breaker, it can be adjusted to 1600A, or does 'adjust' only refer to the breaker setting without considering the change in sensor.

for #4, i want to keep ground fault protection off if it is not required. because with ground fault protection on, it may cause coordination issue.

 

[infinity]

A 1600A frame breaker with an 800A sensor can only be adjusted to 800A. However, the sensor can be easily changed to 1600A. Does this mean that with a 1600A frame breaker, it can be adjusted to 1600A, or does 'adjust' only refer to the breaker setting without considering the change in sensor.

for #4, i want to keep ground fault protection off if it is not required. because with ground fault protection on, it may cause coordination issue.

According to the wording I read this as you would not need the GFPE protection with an 800 amp sensor installed in the 1600 amps frame.

the highest continuous current trip setting for which the actual overcurrent device installed in a circuit breaker is rated or can be adjusted.