Only Two Phases Working on Generator 1

[Bilbag]

On a generator there is no output on the three phase connection and single phase connection. If measured inside the control panel. L1-N is 0v, L2-N is 220v, L3-N is 220v. Generator is required for only light single phase supply 3KW max. 22KVA set. If the single phase connection is moved from L1 to L2 to get a 220v supply and the set is used like this will it cause further damage to the set?
Is likely cause to be a winding failure on one winding? Sorry for so little information I have not been able to inspect the set myself and do further testing.

 

[waross]

First find out why a phase is missing.

Bill
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"Why not the best?"
Jimmy Carter

 

[RRaghunath]

Unbalanced load on generator means negative phase sequence currents which are not good for the rotor of the machine.
Better resolve the issue than risk permanent damage to the generator.

 

[LittleInch]

Well if L1 was being used as the single phase connection and it's now burnt out then that tells you a story.

At 3kW, best to buy a simple single phase generator.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Bilbag]

If the generator had been operating normally wouldn't there be an unbalanced on it when using the 240v outlet anyway?
Also just found out that it needs to run a 4.8KVA inverter welder. hoping to get a look at it soon.

 

[waross]

Unbalanced load on generator means negative phase sequence currents which are not good for the rotor of the machine.

This is not much of an issue on small machines.
We had a 1500 KVA generator on a micro grid.
Due to the demographics of the consumers (peaking at different times of the day) we suffered chronic unbalances.
After several years, a dealer tech reported lower insulation values on the rotor and the rotor was refurbished.
I did not see the test results and was skeptical.
I have never had an issue with smaller machines.
Note that on a balanced load on a three phase machine reconnected for single phase, while the currents appear to be balanced, the kW and real currents are unbalanced.
One winding takes 59% of the real load and the other two windings each take 25% of the real load.
With a unity PF load, one winding is at unity, one winding is at 50% leading PF and one winding is at 50% lagging PF.
The three phase to single phase conversion is standard for any generator above about 15 KVA.
Some users just abandon one phase and use two phasesfor 120/208 Volts.
I have not seen a rotor failure due to unbalanced loads on small machines.

Bill
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"Why not the best?"
Jimmy Carter