Multiple Generators

[shortcircuit2]

Grounded conductors joined from different sources?

Grounded conductors joined from different sources?

Can you guys take a look at the simple one line diagram in post #3 and tell me if there would be a problem with the neutrals of the 3 gen-sets being interconnected?

By using 2-pole transfer switches and set-up as non-separately stand-by power would there be a problem if one gen-set were to lose its neutral or a hot leg?

thanks, shortcircuit

 

[michaelc7a]

The problem with post #3

The problem with post #3

Redundancy generally means that, if one generator fails, another generator comes on in its place. This is the only way to provide an improved chance of uptime for a critical circuit. To have three connected separately is fine if that is what you're after, but it is not improving the reliability of any one circuit. In fact, what usually ends up happening is that all three generators will each have something quasi-critical on it. An example: maybe one will have the network router, another will have the cable modem and another will have the computer. When one gen goes, the whole system is worthless. If this is a residence, the example would be that one would have the garage door opener and one would have the gate opener (just recently had a customer have to hop their own fence when their old gen died during an outage). In this example, the customer would be barely consoled with the fact that their garage door works fine but they can't get their car past the gate.

What we recommend is to prioritize. You can still follow what is suggested in post #3 but add a transfer switch so that, if the #1 priority generator fails, the #3 priority generator switches from its normal load to #1's priority load. This is something we've done for customers that absolutely have to have power for one of their systems. You could even set it up so that the #3 "spare" generator could also power #3's circuits but shed them if the generator becomes overloaded.

Michael Chiasson
AAAA Generator Services
www.aaaagen.com
888.664.2436