Generator Terminal Output Voltage Regulation Problem

What is the type of AVR (auto voltage regulator) used on your unit?

its a digital voltage regulator. I guess 2000 with vars/p.f control.

You need to know what sort/make of control there is before you can make an attempt to understand what may be the problem. The nameplate will probably give you an indication. Better still instruction manuals.

One possibility is that it is linked to other machines and need to be switched to single machine island mode. But this is only a blind and wild guess.

Do not experiment. Raising the output voltage very high accidentally will/may fry a lot of equipment connected to that generator.

I have already switch to single run/Island mode and doesn't made any changes.The DVRs are the same type and for the units has the same name plate except for one unit is a 3516 cat and the other is a 3516B cat but the same configuration. To me not much of a difference in configuration.The unit that is malfunctioning is the 3516 cat and not the 3516B cat.It seems to me that there is an uncontrol of excitation. but why? Caused have already cleared the entire excitation system.Everything seems ok.The excitation components and circuits, PTs,Cts for sensing and drooping, Isoch/droop modes, volts control/P.F control within the DVR and CB/AUX circuits & contacts for inputs that control regulations (That tells the DVR what to do at different modes).What else could caused the uncontrolled of excitation caused the DVR should controlled the excitation.

From here on it gets even more difficult to tell. You may be dealing with a defect somewhere. A fault in the wiring, in the electronics, etc etc.

There are some questions to be asked. Did this thing happen suddenly? Did it happen after maintenance on the unit? Try to determine what started it, when and in what circumstances.

You may have a spare on site. A change of unit may be a short-cut to finding out where the fault lies.

Could It Be that I am having problems with the DVR inputs? Can I regulate the DVR Generator output voltage from the DVR while Unit is runnning online? Caused I want to eliminate all inputs to see if there is any occuring fault from any of them.So I want to know If I would be able to control the voltage by lower or raise the voltage from this parameter on the DVR so that I could be able to ballance the system when needed while on line.

We get to operate the 3516B Cat.Generator unit that was having problem with unstable voltage which was falling when unit was online by itself (on single run) while running in island mode (Isochronous Mode). However we've get to operate the unit, but in volts mode and not in P.F mode.We have disconnected the circuit Terminal No.41 on the DVR that tells the DVR to go into P.F mode. We did not repair the problem as yet with that circuit as yet. However when the circuit is connected, it is not functioning in automatic control (P.F control).How and when does that feature operate (ie..P.F control). it seems that we are having an automatic Power factor control on that unit. How does Power factor mode and Volts mode operate? What could be the problem in that circuit? Could it be that auxillary contacts in that circuit is not closing properly or not making contact properly?

Quote ""in volts mode and not in P.F mode""

When you have a single machine supplying the system, you control the VOLTS of the power out. The DVR which I assume is "digital voltage controller" will do that. Power factor is a measure of Vars (volts reactive) of the system,and the single machine will have to cater for that (no control).

With more than one machine the vars are shared between machines. Then there is some control. the vars are then shared.

You need to understand better what you are dealing with. With lack of full understanding there is risk to machine and to operator.