Low PF on 3ph generator 1

[Emadshaaban1987]

Hi folks,
A 3ph PMG generator driving load with a very low power factor 0.37. The engine fail after 2 to 3 hours. Please see the attached picture.
What are the reasons of low Pf rather than load types .would the low pf course generator to shut down with out a alarm

 

[waross]

Power factor on an islanded set depends on the load.
Worth repeating:
Power factor on an islanded set depends on the load.
What is the rating of the set, in KVA?
The display shows 9 kW and a PF of 0.37. The is a KVA of about 24 KVA.
Going by the Amps and Volts the PF is about 67%.
The Amps and Volts work out to about 13.7 KVA
Is there oil in the engine? Is there coolant in the engine?
Is the airflow to and around the engine restricted?
The PF has absolutely nothing to do with the engine.
As an example: A 10 kW set with a 9 kW load will pose no problem with the engine.
However 9 kW at cos .37 will be delivering about 24 KVA. That won't hurt the engine but it may fry the generator end.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Emadshaaban1987]

Hi
Thank you for variable tips.
The PF for the same load supplied by national grid is almost 0.7.
Can the AVR or diode affect the PF

 

[RRaghunath]

What all signals are grouped under 'Maintenance Alarm'??

 

[edison123]

Reversed CT of one phase on generator side?

Muthu

http://www.edison.co.in

 

[waross]

If you go by the meter readings, 231 V and 34 Amps to get the KVA. it works out to 66% power factor. (Almost 0.7)
Edison's suggestion of a reversed CT is worth pursuing.
Your meter readings are not self consistent.
None of this should impact the prime mover as long as it is capable of producing more than 9kW.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[genhead]

I can't see exactly what model controller you have there but typically the "maintenance alarm" is triggered when a certain amount of running hours are reached, or sometimes a number of calendar days. Some manufacturers set the alarm as a shutdown meaning that the generator cannot be operated until the alarm has been cleared and reset. On most controllers the alarm can be changed to a warning so you can still operate the generator. Your instruction manual should help! Is that the only alarm or were there others?