1083KVA Generator Speed & Freq. Problem

Sounds like dirty fuel or filter, a constriction in the fuel supply piping, or the governor system took a nasty hit somewhere in transit and the linkage has jammed. If the symptoms are identical on both units then you have to look at things that are common to both; i.e., the fuel system and/or the synchronizing system. Since they're brand new it's time to get the supplier/manufacturer involved.

You seem to have neglected the initial primming requirements the same should have been clear to you if you had thoroughly read the commissioning manual from the manufacturer.

Initially you have to turn open the bleed valves located at different points in the fuel piping at the engine in order to release the air in the fuel piping so that diesel occupies all the space.

For the engine lube oil to run through you will have to crank the engine by using a screw driver at two of the starter motor terminals specified by the manufacturer.

Re-work following the commissioning instructions from the manufacturer.

"you will have to crank the engine by using a screw driver at two of the starter motor terminals"

I read your comments, but the engine can be cranked by pressing the start button on the GENSYS panel.Since there are two starter motors for the engine,it might be a difficult procedure which in the end could damage the starter in the process!thanks your comment is noted.

Don't dismiss the they may just need proper bleeding part of the comment, just because of a fairly common 'bush mechanics' practice - when lacking a helper or a remote switch.

But as they do run, you can bleed at the injectors (at idle), which with some fuel systems, is about the only way to get all the air out.

I could think of better ways of ruining a screwdriver.

Why did you accept the generators when they didn't come up to design specification? Get the commissioning team back.

DG set Governor has " maximum speed set point " by mechanical means. May be your DG sets have been commissioned during testing using a defective Tachometer. They should have cross checked the tachometer reading with the frequency meter.

since both the DG sets have the same problem, it could be a wrongly set " max speed "

Check the fuel filters as pointed out by many experts. It seems that your generators do not have under- frequency protection.

Try to find out by what means the speed is adjusted by varying the potentiometer. There can be some mis-match in the mechanism involved.

hey,

first of all check both dg sets one by one idle condition by disconnecting all signals between them (like as synchronouzing & load sharing etc) and lets check the RPM condition @ idle mode, then put on load and lets see what will happen.

We checked all these at pre commisioning stage, the generated outputs were less than 400V. We believe if we can get the speed to 1500 every essential parameters will fall in place. At the moment, we are re-working the commissioning procedures taking into cognizance all suggestions by respondents to this thread. Thanks for your inputs

Hi,

Simplify the problem, the engine or electrical. On engine you may check fuel system fuel line, pump and injector. assume no problem on your fuel line, may be on electrical actuator inside pump, could be dirty, stuck, high impendance, try to compare the data you checked with the manual. In electrical, may be you have different read between on controller and actual, this sometime happend on new set, you could callibrate the reading on it...pls get back if this result ok in your set