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prometu
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Join Date: Mar 2011
Posts: 25

Generator Problem - 30kva Generator

10/21/2011 6:20 AM

We have a 30kva generator, 240v output voltage.

The problem is that, when the generator start, no problem arises not until the load is turned on. At first, the frequency at the generator indicates 64 hz. Then after loading, it drops down until it continuously drops to zero until the generator shuts down.

What might be the cause of this? The loads are airconditioners, lamps, rated 240 volts, 60hz..
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PWSlack
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United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

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#1

Re: generator problem

10/21/2011 6:29 AM

Is the unit overloaded?

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zamanengineer001
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Posts: 26
#2

Re: Generator Problem - 30kva Generator

10/21/2011 6:50 AM

Try to put the load gradually on the generator specially air conditioner should be put atleast after 10 min run,

if problem presist; check the fuel system n its supply, also check the amp if it gets overload. also check other parameters if there is any abnormality in them during loading.
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nesubra
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#3

Re: Generator Problem - 30kva Generator

10/21/2011 9:49 AM

looks like overload.It is a singlephse set? if os is it 0.8PF or Unity pf generator/

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leveles
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Join Date: Jan 2008
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#4

Re: Generator Problem - 30kva Generator

10/21/2011 11:21 PM

In order of likelihood:

Overload. Forgetting Pf, startup currents....

Starving for air, dirty filter.

Starving for fuel, dirty filter.

An Ammeter would definitely help in sorting out. I meant the clamp type.

Detailing, what load (Amps, startupAmps) is turned on at what time intervals is needed to see, when the generator starts to bog down.
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JRaef
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United States - Member - New Member Engineering Fields - Power Engineering - New Member

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Location: California, USA, where the Godless live next door to God.
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#5
In reply to #4

Re: Generator Problem - 30kva Generator

10/21/2011 11:26 PM

In order of likelihood:

Overload. Forgetting Pf, startup currents....

Starving for air, dirty filter.

Starving for fuel, dirty filter.

An Ammeter would definitely help in sorting out. I meant the clamp type.

Detailing, what load (Amps, startupAmps) is turned on at what time intervals is needed to see, when the generator starts to bog down.

Below those:

Bad governor

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Far
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Join Date: Sep 2011
Location: Ontario
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#6

Re: Generator Problem - 30kva Generator

10/22/2011 12:54 AM

The governor is not responding at all, the engine does what it can with the fuel setting it has when starting up - that is enough to bring it to 1920/3840rpm depending on your generator. You did not say whether the frequency drops down to 60, as it should when running with no load, but that would be another indication of the same problem.

Before you try to start the engine again, check the linkage from the governor to the fuel sytem and especially check that everything is free to move as it should. If the linkage seems to be connected and working properly you need to overhaul the governor.

You may have been lucky the engine did not destroy itself by running too fast.

Now get a proper mechanic to fix it for you.

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prometu
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#9
In reply to #6

Re: Generator Problem - 30kva Generator

10/23/2011 8:15 PM

thank you sir..
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dhayanandhan
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Engineering Fields - Mechanical Engineering - New Member

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#7

Re: Generator Problem - 30kva Generator

10/22/2011 1:47 PM

Dear Mr. Prometu,

Pl. provide more details.

1. What is the type of load for which this 30 KVA set is to supply power.?

2. If motor is to be started - what type of starter is used.? and what is the H.P of the motor.?

3. What is the Power Factor of the system.?

The above details may help to identify the problem.

DHAYANANDAN.S
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prometu
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#8

Re: Generator Problem - 30kva Generator

10/23/2011 8:14 PM

thank you for the response.. i appreciate it. i need to sort out all of your comments for me to be able to see the real problem
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dhayanandhan (1); Far (1); JRaef (1); leveles (1); nesubra (1); prometu (2); PWSlack (1); zamanengineer001 (1)

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