PTO generator

[aczlan]

If you are looking for something diesel, look at a MEP-004(15KW) or MEP-005(30KW) Military Surplus generator.
Both ratings are "Prime" (ie: what it can put out 24x7) at 5000' of elevation and 120F ambient temperature. Both models are also 3 phase and soildly built.
Sewerzuk on here has quite a bit of experience with them.

Aaron Z

 

[jmcmurray]

The province did a study of the quality of power (and many other factors) when using PTO driven generators.Tractor-Driven Generators: Producing Quality Power

Somewhere in there they even try the 1000 PTO run at half throttle idea.

 

[SPYDERLK]

The province did a study of the quality of power (and many other factors) when using PTO driven generators.Tractor-Driven Generators: Producing Quality Power

Somewhere in there they even try the 1000 PTO run at half throttle idea .

Very unstable to load changes.

 

[SPYDERLK]

Thank you larry, that is a great idea. I hadn't considered a custom pairing, but it will be unlikely that I will find a pre-owned system like that. Do you have any advice regarding the VFD?

Variable frequency drive? ... Soft start technology? I think this can definitely limit the hi inrush. It is very applicable on fans and anything that starts similarly under "no load" conditions. Many pumpers of liquid can qualify as starting under semi load -- a harder start scenario not necessarily applicable to the SST ... but maybe. Study up and youll easily know more than I.
... I still cant get a grasp on your elevator motor start and I think the load mode it starts under will be very important. Does the motor only run when the elevator is moving? - or start 1st and then you select up/down.
larry

 

[RickB]

Very unstable to load changes.

Not much different from any other engine driven genset. The closer one gets to using all the available engine power, the more variable the product is. I monitor voltage and frequency with an inexpensive Kill-A-Watt unit plugged in a kitchen outlet.
I get along fine with my 885 Case running my alternator at 1100 ERPM so long as I don't run my central A/C unit.

 

[fred239]

... I still cant get a grasp on your elevator motor start and I think the load mode it starts under will be very important. Does the motor only run when the elevator is moving? - or start 1st and then you select up/down. larry

The motor only runs when the elevator is moving up or down, it runs a hydraulic pump. It's only a three storey elevator, like a big hydraulic jack.

 

[SPYDERLK]

Not much different from any other engine driven genset. The closer one gets to using all the available engine power, the more variable the product is. I monitor voltage and frequency with an inexpensive Kill-A-Watt unit plugged in a kitchen outlet.
I get along fine with my 885 Case running my alternator at 1100 ERPM so long as I don't run my central A/C unit.

Theres a combination of factors that make it less stable; 1] As you say, you are using a higher proportion of the power available as a result of almost twice the engine torque required at its lower rpm, 2] due to the higher pto gearing the gen rpm changes almost twice as much with a given change in engine rpm. ... Even if the engine has the power to support the full load range youre asking twice the exactness from the governor.
larry

 

[RickB]

Theres a combination of factors that make it less stable; 2] due to the higher pto gearing the gen rpm changes almost twice as much with a given change in engine rpm. ... Even if the engine has the power to support the full load range youre asking twice the exactness from the governor.
larry

That is a variable I hadn't considered.
In my particular circumstances, I don't forsee any changes. The power quality is sufficient, the tractor maintains a decent engine temperature, and there is no slobbering or wet stacking. And it ran on about 2 quarts per hour of Diesel fuel over 18 or so hours of run time during and after Sandy. In fact I just changed the fan belt on it today as an act of preventative maintenence. Certainly don't want it to toss a belt while I am inside nice & comfy watching TV.

 

[SPYDERLK]

The motor only runs when the elevator is moving up or down, it runs a hydraulic pump. It's only a three storey elevator, like a big hydraulic jack.

... Does the motor reverse direction or is elevator direction controled automatically by valving according to which button u push. If you push down on the lowest floor does the motor start? Sofar its sounding like a full load start anytime youre going UP. What happens when the elevator is heavily loaded?
larry

 

[fred239]

... Does the motor reverse direction or is elevator direction controled automatically by valving according to which button u push. If you push down on the lowest floor does the motor start? Sofar its sounding like a full load start anytime youre going UP. What happens when the elevator is heavily loaded?
larry

Motor does not reverse, does not start on down on lowest floor. Maybe a full load start, will check about an unloader start valve. My guess is that heavy loads will use only slightly more current as the car and jack shaft are pretty heavy already. Thanks for your advice, and Happy Thanksgiving.