AARGH Generator doesn't want to start vacuum pump

[Bruce L]

After two days of getting the 4 wheel drive tractor stuck carrying the generator into the bush, we finally got the generator in today into it's shed . I started up the generator, while allowing it to warm up I plugged in the outlets for the pump, sugarhouse etc in to their respective outlets. My Father asked me if it would be too cold, pump froze up, it is cold here and snowing, but I turned the pump over several times by hand, though I didn't hear the veins clicking it turned freely. Then came the moment of truth, I threw the switch and the motor started to roll, the generator working hard, but didn't seem to want to kick up. I flipped the switch off so I wouldn't do any damage, then tried again to no avail. Looking back I guess I should have slipped the belts off, on another day( maybe warmer) I might have to get my brother-in-law the electrician to measure how much the motor is drawing trying to start I find it hard to believe that this generator won't do the trick. It is a Winco 12000 watt generator, 20 hp Honda gas engine, with a 60 amp outlet that I am plugged into for the pump. The pump is a De Laval 76 with 3 hp motor on, I believe it is either a Leeson or Doer? I would have to check. Should the generator be able to do it no problem on a warmer day, or maybe motor is drawing too much?

[maple flats]

What are the starting amps on the motor? Being PTO powered you need a little more reserve because the tractor will not respond to a load as fast as a engine driven generator would. You may need more generator or maybe an additional capacitor. If the motor does not have capacitors you may need a different motor. The first is to get the FLA amps (full load amps) and the starting amps off the name plate.

[maple flats]

Another issue could just be the cord between the motor and the genny. How long and what gauge is the cord. That coupled with the starting amps will allow me to let you know what gauge cord you need.

[Flat Lander Sugaring]

to use a Gen to run any motor load the generator must be sized like 175% more than start current if I remember that right. One quick way to burn a motor up. I did a calc a few years ago for VT St. Fire Academy they wanted to run some props at fire houses they go to teach at and the size I came up with was pretty crazy.

[BAP]

Did you run the pump before you took it to the woods? Do you know if the motor is good? Also, is it wired correctly for 220v? Do you have an electrical tester that you can check the outlet on the generator to make sure it is putting out 220-240volts? Sounds like a voltage problem or a bad capacitor on the motor.

[mnguy]

Here is a 230 volt motor chart

[Bruce L]

Took a look at the motor this evening, it is a Magnetek Century AC motor, unfortunately the sticker has faded so much that I cannot read the amperage on it. My brother-in-law(the electrician) wired from the motor to a breaker panel that I use as on/off switch with about 8' of #8 stove wire, then from there it is maybe 10' or less of #10 wire to the 60 amp plug on the generator. There is only 1 capacitor on the motor, looks good, but I know you cannot go by just looks. I haven't run the pump or motor since last sugar making, I will have him come with his tester and slip the belts off and check everything over before the sap starts to drip much. We both find it hard to believe that a 20 hp Honda gas engine on a winco 12000 watt generator won't start a 3 hp motor, have to do more investigating.

[sjdoyon]

We experienced something similar, we have a 30,000kw generator which can max 134 amps. We tried to run a 10hp vacuum pump which requires 39 amps to run. Generator grinded down and almost shut off. Was then told that the start up requirements are higher than our capability. As i was repeatedly told by dealers when I asked, I'm no electrician but you are probably drawing too much power for your generator. Be careful on trying to run it off your generator, you can burn the motor on your pump.

[maple flats]

Does he have a clamp on amp meter? That can tell exactly what is happening. If the generator is marginal, you might be able to use a manual clutch. Start the motor, no load and then tighten the belt with the manual clutch. It might well do it that way. Then you have far fewer starting amps and then the only issue is the FLA (full load amps) which are considerably less. The 12,000 watt generator should give 50A running. A 3 HP motor will be less than that. It should be 17A and you should be at 125% of that or just over 21A, but the surge could be as much as 3x that. The capacitor could also be faulty.

[Flat Lander Sugaring]

Took a look at the motor this evening, it is a Magnetek Century AC motor, unfortunately the sticker has faded so much that I cannot read the amperage on it. My brother-in-law(the electrician) wired from the motor to a breaker panel that I use as on/off switch with about 8' of #8 stove wire, then from there it is maybe 10' or less of #10 wire to the 60 amp plug on the generator. There is only 1 capacitor on the motor, looks good, but I know you cannot go by just looks. I haven't run the pump or motor since last sugar making, I will have him come with his tester and slip the belts off and check everything over before the sap starts to drip much. We both find it hard to believe that a 20 hp Honda gas engine on a winco 12000 watt generator won't start a 3 hp motor, have to do more investigating.

Am i missing something? #10 (30 Amp wire) to a 60 Amp plug?

[Bruce L]

Brother-in law (the electrician) was here today, figured it is just the carburetor and governor on the generator. Draws 34 amps to start the motor, and 17 to run it. Turned on the blowers on the arch, pretty slow starting the high pressure blower, checked the voltage and it was down to 86 volts, until the generator ran smooth again up to 117 volts then. Had to hold the governor spring on all of the way to get the pump started, so will have to get that adjusted as well as maybe clean the carburetor again. Biggest problem with this generator was probably the amount of idle time that it sat with old gas in it before I purchased it.