Governor system in off road diesel engines

[Uncia_Uncia]

Hello,
I am going through the technical data sheet of one of the off-road diesel engine manufacturers and came across the governor setting. I have attached image for reference. I checked another thread about the droop vs the isochronous governor system and all are related to generator sets which make sense as it is related to maintaining constant frequency with varying load.
Can anyone, please, explain to me how can I relate governor system data with off-road diesel engines?
It will be wonderful if someone can explain the attached datasheet.

Thanks

 

[T VS]

I can’t help directly with your question, but all ‘mechanical’ diesel engines are driven off the governor. The ‘throttle’ lever pulls on a spring that is connected to the flyweights on the governor. From my knowledge and experience of driving, it doesn’t give a perfect constant speed setting - and even less so with pumps like the Bosch VE which are designed to give more engine ‘power’ than determining a change in RPM with increasing throttle position.
Not sure what you mean by “off road diesel engines” but I’m talking about Landrover type diesel engines of 2-2.5 litres and old CAV and Bosch VE pumps. Does this help at all?

 

[GregLocock]

The droop setting tells you how much torque the governor will add in response to a drop in rpm below the target rpm. Trucks and tractors used to use generator type governors, the 'throttle' pedal is in fact a target rpm pedal. However when diesels hit the consumer market drivers wanted a similar throttle feel to a gasoline car, ie more pedal=more torque. So they changed how the pedal and injector pulse width interacted. Nowadays it's just a model and a lookup table, essentially.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[TugboatEng]

There are two major governor classifications, a speed limiting and a constant speed. In the speed limiting case the operator controls the injection quantity (rack position) and the governor intercepts when speed goes above or below the high and low idle settings.

Within the constant speed category there are speed droop and isochronous. In both cases the operator controls the height of the speeder spring. The isochronous governor has a compensation circuit that returns the engine to the speed setting regardless of load.

All governors have speed droop. Governors with compensation operate in speed droop during load changes and compensation occurs after the change. Even in the case of speed limiting governors, it's common to have a high idle of, for example, 1925 rpm while full load speed is going to be 1800.