Petrol generator frequency

[starcott]

I'm considering buying a used petrol generator but there seems to be some confusion as to what the output frequency is, 50 or 60 Hz.

Is there any way of finding out the output frequency of a generator?

If it did turn out to be 60 Hz, could it be changed to 50 Hz, and if so, what needs to be done?

Thank you.

 

[Engineer54]

You don't say your location, but if your in UK and buying from a UK supplier, it is unlikely they would supply a 60Hz unit unless it's for a specific purpose...

 

[DurhamSparky]

with E54 on this one...!!

 

[Geordie Spark]

I'm considering buying a used petrol generator but there seems to be some confusion as to what the output frequency is, 50 or 60 Hz.

Is there any way of finding out the output frequency of a generator?


If it did turn out to be 60 Hz, could it be changed to 50 Hz, and if so, what needs to be done?

Thank you.

Maybe read what is marked on its rating plate?

 

[Knobhead]

I’d go by the rating plate.
As to what to do if it is 60Hz that depends on what you intend to do with it. Some you can alter the engine speed governor.

 

[steve-the-hat]

I'd take along your MFT, a fan heater and suitable adapters to test it.

On some genys the frequency and output voltage change with the load.

 

[Deleted member 26818]

I'd take along your MFT, a fan heater and suitable adapters to test it.

On some genys the frequency and output voltage change with the load.

Yes often the higher the load, the lower the speed, hence the lower the frequency.
It may be that the frequency is high for no load, but drops as load is applied.
Many appliances are rated at 50-60Hz.

 

[WDMDL]

If it's got UK or Euro sockets it should have been set to a nominal 50Hz (3000rpm engine speed).
You can expect some undershoot and overshoot of frequency as the loading changes, but should quickly return to the nominal.

More importantly, check that the spec mentions AVR - Automatic Voltage Regulation.

On the cheapie (650-850W) 2-stroke models common on the market, they do not have AVR and given a change in load or severe "hunting" caused by an incorrect petrol to oil ratio, there can be some disastrous overshoots of voltage as the engine overspeeds for a couple of seconds - over 300V even when loaded at 500W.
Not so bad when that blows a 500W R7s halogen lamp, but that could also be your TV, Hifi, computer....

Simon.

 

[Engineer54]

You don't specify the KW rating of the Genny your planning on purchasing. Normally a Genny with a decent KW rating, will have at least a half decent AVR, but on the lower rated units you probably won't see one included....


Do you have a preferred make and model number, of the unit you're interested in, if so post it up and we'll see if we can give you any further advise??

 

[geofff]

WDMDL, how do you know its 3000 rpm? given that f=np/60 where f=frequency n=speed p=pole pairs 60 is time constant.
Unless of course you know how many pole pairs this genny has and you can then use transposition of formula to work out the speed?

just wondering ;-)

 

[starcott]

Thank you for all the help and suggestions.

I managed to get confirmation that the generator is 50 Hz so all is now sorted.