Got my hands on a clamp-on ammeter today and did a little data collection; before I get to that, I'll provide the following info on motor draw vs load so y'all can see how the motor is loading under various conditions (I happen to have complete specs on this motor):
no load: 4.5amps
0.25 load: 7.0amps
0.5 load: 10.85amps
0.75 load: 15.5amps
1.0 load: 20.53amps
Motor is nameplated 230 volts, 5hp, 3450RPM, 20.8 full load amps (single phase cap start/cap run design).
The data:
motor idling, spinning pump only: 6.3 to 6.4 amps
extend stroke: 7.0 amps; return stroke: 7.9 amps (reading taken within one minute of start up).
After letting the motor operate for 5 minutes or so, current draw decreased a little (as expected): 6.6 amps on extend stroke and 7.4 amps on return stroke.
I picked up a load of elm over the weekend, so I thought this would be the best species to test with: ran three test splits (see attached pic) and motor draw was 8 to 9 amps on the split stroke, with the highest recorded value of 9.4 amps and 1600psi to 1700 psi on the gauge on the toughest of the three splits, those values only lasted about one second and then decreased quickly, so I would almost call these spike values. I tried to stall the pump or motor by keeping the valve open when fully extended as well as fully retracted, only for a second or so just to get a reading on the ammeter.......could not get it to exceed 15 amps (2700psi on the gauge). So even under worse case conditions, this particular motor does not exceed 3/4 load.
I had 240 volts to the motor per my measurement at the outlet, but that ain't going to skew things much for this experiment.
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