GENERATOR RUNNING

[hawkeye23]

I would like to get some experienced electricians, engineers to comment on a work application where a emergency genie is used. The genie is for a 480 volt3 phase system. Sized I believe to be in the area of 2000 kw. The generator comes into service to supply power to the plant main switchgear that has been determined to be hazard cat 4 by the arc flash study. What does the operators of the genie have to be dressed in as far as ppe ? Is there any other requirements to go along with this work as far as interacting with genie or switchgear ?
There also a control panel to start the genie for testing that is about 10' from the switchgear, Is this something where ppe is needed ? From what I see there isn't any ppe being used when genie is in service for testing.

 

[mbrooke]

I would like to get some experienced electricians, engineers to comment on a work application where a emergency genie is used. The genie is for a 480 volt3 phase system. Sized I believe to be in the area of 2000 kw. The generator comes into service to supply power to the plant main switchgear that has been determined to be hazard cat 4 by the arc flash study. What does the operators of the genie have to be dressed in as far as ppe ? Is there any other requirements to go along with this work as far as interacting with genie or switchgear ?
There also a control panel to start the genie for testing that is about 10' from the switchgear, Is this something where ppe is needed ? From what I see there isn't any ppe being used when genie is in service for testing.

If the generator is running, use ppe. The arc flash may or may not be as big as the utility, but a diesel generator can certainly produce some good fault currents.


When its off and guaranteed not to start, still use some basic ppe. There are still some line volt control circuits that can bite. DC starting to can give a good spark if not handle right.

 

[jim dungar]

If the generator is running, use ppe. The arc flash may or may not be as big as the utility, but a diesel generator can certainly produce some good fault currents.

In almost all cases, the Arc flash Incident Energy from the generator will be in excess of that from the utility.
there is not enough fault current to cause protective devices to operate in their instantaneous region, therefore clearing times greater than 2 sec are not uncommon. Except for paralleled generators, I think >25cal/cm? is not unexpected.

 

[mbrooke]

In almost all cases, the Arc flash Incident Energy from the generator will be in excess of that from the utility.
there is not enough fault current to cause protective devices to operate in their instantaneous region, therefore clearing times greater than 2 sec are not uncommon. Except for paralleled generators, I think >25cal/cm? is not unexpected.

Make sure the generator is mounted well too. A hard fault can actually tip one over thats unsecured.

 

[kingpb]

I would like to get some experienced electricians, engineers to comment on a work application where a emergency genie is used. The genie is for a 480 volt3 phase system. Sized I believe to be in the area of 2000 kw. The generator comes into service to supply power to the plant main switchgear that has been determined to be hazard cat 4 by the arc flash study. What does the operators of the genie have to be dressed in as far as ppe ? Is there any other requirements to go along with this work as far as interacting with genie or switchgear ?
There also a control panel to start the genie for testing that is about 10' from the switchgear, Is this something where ppe is needed ? From what I see there isn't any ppe being used when genie is in service for testing.

it is not possible to say without looking at the set-up and doing an analysis. Speculation is not a good idea when dealing with life safety.

You need to hire an engineer that is experienced in this area.