Generator advice

[jamied]

please can anyone tell me which they think is best ?

I have been told that 3000 rpm generators are better than 1500 rpm generators.

The reason is that the 1500 rpm units are not loaded enough so can often get bore glaze reducing engine life even though they are mean't to last longer.

any comments ??

 

[William_H]

You are obviously talking 240VAC generators here. If the generator is direct coupled to the engine then to get 50 cycles per second if you have 2 pole generator it must run at 3000RPM while if you have a 4 pole generator (it does its cycle thing twice every turn) then you must run a 1500 RPM.
The engine manufacturer is the one who can advise the outcome of running the engine at those speeds long term and of course it depends on whether the engine is loaded to anytghing like it's power capability.
Of course if the generator is belt driven then by choice of pulley sizes the engine can run at any speed while still giving the 1500 or 3000 RPM required. So no answer to your question but may clarify the story. olewill

 

[TrueBlue]

[ QUOTE ]
please can anyone tell me which they think is best ?

I have been told that 3000 rpm generators are better than 1500 rpm generators.

The reason is that the 1500 rpm units are not loaded enough so can often get bore glaze reducing engine life even though they are meant to last longer.

any comments ??

[/ QUOTE ]

Yes, plenty of comments:-
For a reasonably quiet life 1500 rpm sets are the best - a 3000 set will be much, much noisier. However a slow revving unit will be bulkier and heavier.

You only get bores glazed where an engine is run for long periods at lower loads than its design point. For proper industrial units - as in your case, a generator set which runs at constant speed - the design will match the engine running characteristics with the design load.

Sooo, I think your advice was based on half-knowledge of the issues.

 

[bpscmarine]

We would suggest you talk to Genacis at enquiries@genacis.com Please mention we sent you / bpscmarine services

 

[boatmike]

Frankly that's rubbish. William H has aptly described the difference in the electrical side. Mechanically the engines chosen are designed to run at the speeds chosen so will not have a problem with bore glazing or anything else if they are reasonably well loaded. The big difference is that 1500 RPM sets are heavier, generally more expensive and marginally quieter but the noise level of either will rely more on a good enclosure than the RPM and the soundproofing on most (like the Onan sets) is excellent. You have not said what output you need. Frankly if it is only low don't buy too big a set. Bore glazing will be a problem if you are constantly running either at 10% load.

 

[mocruising]

Read all the stuff that has been published wrt the surveys carried out following the ARC's. I think Westebeke have come out on top for a few years.