×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

neutral connection in generator set paralleling

neutral connection in generator set paralleling

neutral connection in generator set paralleling

(OP)
Hello
I am planning to connect the neutral of the entire three synchronized cat 608 kva similar generator set  on the common ground bus bar (the ground will also be connected to the bus bar) without any neutral-  grounding contactor (this is because I am using 3 pole contactors for the main synchronization). I have tried to gather information about this idea on the internet and I have seen different ideas posted which contradicts. Will this create problem?
Please advise me from practical point of view.
If it is possible advice me, any ways which could avoids the possible risks without using the neutral contactor
Thanks in advance
 

RE: neutral connection in generator set paralleling

If these generators are connecting to a bus that is also has a utility source, you need to coordinate the service entrance grounding, main bonding jumper and ground fault protection sensing.  

Establishing a separate ground point for the three generator neutrals sets up a possible problem for other ground fault protection that might be provided if there is a separate utility service.  

Since the three generators are identical CAT units, issues related to harmonic currents should be minimal.

 

RE: neutral connection in generator set paralleling

I would recommend a disconnect switch in each of the generator neutrals.  If a generator is taken down for electrical service, then one opens the neutral disconnect to completely isolate the generator section.  Normally I have seen one pole of a standard 3pole disconnect used.  If one wishes, one of the other disconnect poles can be used to trip the main cb if the disconnect switch is opened.  Or an auxillary switch can be added if an NC contact is needed for a main CB lockout.

iceworm

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources