DG Set Issues When Using a Diesel Generator

Please describe the characteristics of the load. Are there any motors in it, for example?

If there are any motors in the load it may be worth considering VSDs or soft-starters as a way of keeping the current down at start-up. Sequence-starting the motors is also a solution.

yes you can gradually load a DG to full load, however, if you block load it, the first applied load shall not be more than 40%-50%, varys bet different DG makers... some maker like Caterpillar may have better block loading DG... but, according to ISO8528, the block loading capability relates to engine's mean effective pressure when firing (BMEP), todays engines are mostly turbocharged with higher BMEP, so it's quite common now for clients to encounter this block loading problem.

tips: always start larger motor first because of the larger available KVA from the DG, take SKVA and block load into consideration when you are sizing a DG for your plant; if you have lower pf, you can ask DG supplier to provide you an oversized alternator DG which gives you more KVA than KW.

Electrical loads do not work with inching type of input and they require the full power for its delivary which is not required in any other power delivary system suppose a car -it requires a small input of power at the begining.So your DG should have higher capacity to deliver your total electrical load or else what you are doing now to put DG in full load in steps.

What is the cause of the shut down?

Is it Under Freq, Under volt, Over Current?

Is info is needed in order to give a meaningful diagnosis.

If it is under freq, you may just need to adjust the 14 relay with a time constraint to let the engine pull through the applied load.

If it is under volt, you may need to adjust the 27 relay or the amount of droop in the VR. Typical in standby generators is 4% Droop.

Are the controls set for ISOCH or DROOP?

When you load the load the machine, what are the PF, Kw, KVAR and Hz values.

Also of interest if available the percent of fuel command at full load.

What type of gov is on the engine?

T.

i am an ex Caterpillar guy i would suggest you contact Your FG Wilson dealer and ask the engine block loading capabality ,most probabaly the engine is Caterpillar Perkins Caterpillar should be in a position to help you best.

crm

Greetings,

I have Solar Turbines in my past, RFE. Most of my exposure was power gen applications from the 750 Kw Saturn to the 17 Mw Titan 130.

Both Island and inport/export mode.

Also spent some time with CAT working on D399, G399 gen sets.

Greetings,

What is on the unit for generator protection?

T.

Almost every electrical load, (even incandescent lighting), has some

'inrush`, (starting current greater than full load running).

This 'inrush` is probably greater than your gen. set rating, so it 'trips out`.

Step load the gen. set.

Pragmatist has probably hit the button, starting or inrush current on some AC motos is usually about 6 times the running current and can get to 8 times on some designs.

To work as you seem to want, you would need to have a generator that is aproximately 6 times heavier than you actually have......

Its better to softstart your motors so that the starting current surge is reduced.

Transformers have also a Starting current too.....

Live with that I would say.