Never flash an excitor field without having diode polarity protection on your battery leads.
Its preferred to flash a field without the AVR in-circuit; but if it is the diodes are definitely required, or as waross said............
eric
alehman,
Yes, we can, when allowed to go back out and work on it.
Very peculiar operation. I will revive/update the thread once we've been able to get hands-on again.
Thanks to all again for responding,
eric
Most 4 pole systems where the neutral is switched, are considered separately derived sources. The neutral and generator frame ground are bonded at the genset, and usually the genset system will have its own earth electrode.
Determine the kind of existing utility/building grounding connections...
How are they being connected? Cable & plug, 3-pole transfer switch, 4-pole transfer switch, and where are you located (AHJ issues) will all make a difference.
eric
alehman
Yes, always the same breaker (the Utility Breaker, as previously stated). Apologies for not making that clearer.
Square D, Master Pact series breaker, STR-38 is the protective Trip Unit model installed in the breaker--the basic one: long/short time current functions, and GF residual...
itsmoked,
Thanks for responding. No, it seems to trip, randomly, at the moment the starters are released, either by turning the manual start switch back to off, or letting it fire up and the speed switch disconnects them. Doesn't matter, how it starts, its that release that causes it. We can...
Greetings all experts,
We have a customer who has an issue with one of the back up power systems at their site. This is a 480V 2MW genset and closed/soft transition transfer switch. Switch has the utility-side service breaker integral to the transfer switch cabinet. (MasterPact with a STR-38...
You didn't say, but I'm presuming this is a "Detector" control.
As waross suggested, Check the fuses on the board inside the control panel. There are a few, but the one you'd be looking for is for the switched B+ (I believe). These boards are pretty durable, and I doubt it went bad because of...
davva,
The day tank should not be gravity fed to the genset fuel inlet for reasons of potential leak-through of fuel on the engine if a soleniod or other device was not holding fuel back cleanly at shut-down, as it should. You should not need to add external pump to get fuel from the day tank...
Is this a large quantity of fuel? As for quality, if the client is determined to keep this fuel, then have an analysis done on it. A thorough analysis will give you the current cetane (= to octane in gasoline), amounts and types of contaminents, water, biological and fungal critters living in...
Keith,
For what it's worth, all the diesel-driven fire pump systems I've ever worked on have dual battery systems; ie, 2 individually charged and operated 12 volt batteries for a 12 volt system, and two sets of batteries (series/24V) for the 24 volt systems (also, two separate chargers). I...
I like the traffic light analogy too: you cross the intersection when it is clear, and a breaker indicator is green when it is has cleared.
As for the origination, don't know, but it's been almost always been around power plants as far as I can tell. Looking at my antique book library...
From the "for what its worth", I agree with an earlier post and would scrutinize the genset's governor settings. You stated this is a 2MW diesel, running at about 50%. I would not expect to see the .4 Hz swing on that genset; possibly if the stability and/or gain were a little off, and the load...
