Generator earthing

[sunnyoz]

Gday all,
New in my posession 2 x 250KVA generators they are to be set up totally independentlly from normal supply with one duty gen and standby gen switched through a 4 pole transfer switch. In OZ und NZ we have a MEN earth system or PME european equivalent. My question should the MEN link be on each generator or on the main switchboard ? I have referred to AS/NZS 3010 Electrical instillation Generator Sets and examples are for interruption to normal supply generator instillations, any help greatly appreciated
Sunnyoz.

 

[pugwash]

G'day Sunnyoz,
Not sure if your transfer switch gives isolated changeover or a degree of parallel running. If there is a chance of parallel running, I'd advise making your Neutral-Earth connection in the switchboard with restricted-earth fault protection on each of the generator feeders.
If it is a simple changeover situation, then each generator could have its own N-E connection and the REF protection would then be unnecessary.
The aim is to provide only one N-E connection on the system at any one time.
HTH
Pugwash

 

[powerjunx]

sunnyoz, is this a newly installed units or it is about to be installed? Or are you carrying out revisions?

regards,





"Whenever you are asked if you can do a job, tell them, certainly I can! Then get busy and find out how to do it." Theodore Roosevelt.

 

[sunnyoz]

Gday pugwash,
Thankyou for your reply, the transfer switch is total isolated transfer with a ten second delay on switching.Thanks again have a good one.
Sunny oz