generator, 480 v, 200 amp

shalomfred

Member
Location
Dillon Montana
Occupation
electrician
I was asked to hard wire a three-phase generator for a city septic system. It is currently hooked up with a so cord. The generator has three phase wires with a chassis ground, in the service the ground is connected ground with a neutral being derived there. Do, I need to try and pull a neutral from the generator? Am I calculating the wire size correct at 250kcmils.

you all are great helping with our issues, thank you
 
Is the generator neutral bonded to the frame?
Are there any 277 volt loads? Is the transfer switch 3 or 4 pole?
 
transfer switch is 3 poll, the motors (pumps) are 277v, I do not know about the generator neutral, there was generator person there calibrating the generator I could not get in there
 
Then the generator would be wired as a SDS, with bonding and grounding at the building service. The neutral is only bonded are the service. There is a requirement in Art 702 for signage.
How big are the pumps? 277 is a uncommon pump / motor voltage. You asked about pulling a neutral..,it’s needed for your pumps and a a ground fault return to the generator windings
 
will ask about the pump voltage, I will ask the generator company about the generator how it is wired, the reason I am asking these people is because this town is an hour away, I will go out if I need to, let me know other things I need to find out
 
Find out size (amps) of generator circuit breaker
Does the generator have a heater and battery charger (probably) if so you will need to provide a circuit, get amps and voltage of those.
Will the owner want remote alarms and monitoring?
Get a picture of generator nameplate
If there is a control panel, get s as wiring diagram
Others will comment.,,
 
If it is LP fired, make sure there are provisions for keeping the regulator warm (wrap in heat tape then duct tape) and be sure the heat tape is fed from the correct source ( if there is also utility power).
 
A little info on this job; it is a lift station for the town, it pumps waste about 2-mile up hill to be distributed in a alfalfa field.

The generator is fueled by diesel, it does have a charger, no alarms needed.

This generator is already set up with a temp cord (so) to feed the transfer switch, however the connector is soo corroded that it does not work so that is why they want to hard wire it. Everything is already set up just needs new wire.

The main breaker for the generator is a 200 amp. I have pictures hopefully I can download them. the photos are too large for your server.

generator;
mod number; 150R0ZJ01
spec num; 189807-01
ser num; 280877
 
Last edited:
A little info on this job; it is a lift station for the town, it pumps waste about 2-mile up hill to be distributed in a alfalfa field.

The generator is fueled by diesel, it does have a charger, no alarms needed.

This generator is already set up with a temp cord (so) to feed the transfer switch, however the connector is soo corroded that it does not work so that is why they want to hard wire it. Everything is already set up just needs new wire.

The main breaker for the generator is a 200 amp. I have pictures hopefully I can download them. the photos are too large for your server.

generator;
mod number; 150R0ZJ01
spec num; 189807-01
ser num; 280877
Are you going to use a raceway for the conductors or use cord again?
 
I am wanting to run conduit. it is outside. the wire size I calculated is 250 kcmils I want to make sure that is correct, for one thing. just for materials it will come out to be $3600.00 it is a small town so I am trying to downsize wire size and conduit to decrees the cost.
 
Is the generator neutral bonded to the frame?
Are there any 277 volt loads? Is the transfer switch 3 or 4 pole?
A little info on this job; it is a lift station for the town, it pumps waste about 2-mile up hill to be distributed in a alfalfa field.

The generator is fueled by diesel, it does have a charger, no alarms needed.
yes the generator is neutral bonded to the frame
I do not know about the motor voltages yet

This generator is already set up with a temp cord (so) to feed the transfer switch, however the connector is soo corroded that it does not work so that is why they want to hard wire it. Everything is already set up just needs new wire.

The main breaker for the generator is a 200 amp. I have pictures hopefully I can download them. the photos are too large for your server.

generator;
mod number; 150R0ZJ01
spec num; 189807-01
ser num; 280877
 
will ask about the pump voltage, I will ask the generator company about the generator how it is wired, the reason I am asking these people is because this town is an hour away, I will go out if I need to, let me know other things I need to find out
Personally, I think a preinstall site visit as part of the contract is not only reasonable but a very good idea. Should be built in to the cost of the work.
 
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