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Perkins 2800 series need to run at 900RPM
- Thread starter alaa
- Start date
OzDozer
Senior Member
Probably because he's changed the alternator from a 6 pole to an 8 pole?
Would that not only get him to 50 hertz
I suppose if he is not in the US it whats used
OzDozer
Senior Member
No and Yes. I presumed when he wanted to change from 1500RPM to 900RPM, he was originally operating at 50Hz and wanted to go to 60Hz with a different alternator. Maybe I presumed too much, I don't know.
We use 1500RPM, 4 pole alternators down under here, because we run at 50Hz and 240V, single phase.
Frequency = (RPM x # of poles) / 120.
So - (900 x 8) / 120 = 60Hz.
If he wants to run at 900RPM, it's easy enough to reset the throttle to that limit, the main thing is, is the engine fitted with a genset governor?
Genset engines are normally fitted with a governor with tighter limits as regards RPM drop, before the governor cuts in. This is done to ensure voltage doesn't fluctuate excessively with varying loads.
Genset governors usually have a 3% RPM variation limit, whereas tractor and automotive engines can have up to 10% RPM variation limit. It all depends on the engine make, style of IP, and makers settings.
We use 1500RPM, 4 pole alternators down under here, because we run at 50Hz and 240V, single phase.
Frequency = (RPM x # of poles) / 120.
So - (900 x 8) / 120 = 60Hz.
If he wants to run at 900RPM, it's easy enough to reset the throttle to that limit, the main thing is, is the engine fitted with a genset governor?
Genset engines are normally fitted with a governor with tighter limits as regards RPM drop, before the governor cuts in. This is done to ensure voltage doesn't fluctuate excessively with varying loads.
Genset governors usually have a 3% RPM variation limit, whereas tractor and automotive engines can have up to 10% RPM variation limit. It all depends on the engine make, style of IP, and makers settings.
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usually we use to decrease the RPM when we go to start testing the injectors cutout test also some company they ask to start the engine after finish major overhaul.
That's why I need to change the rpm