KBMM-225D and 2.8HP Treadmill Motor
I've been working on this upgrade for a while, and finally got to test it out tonight (no milling yet, and no load on the motor). This drive is supposed to be for 90v or 180v motors, and since mine is 130v (2.8HP continuous duty) I tried it on the 90v setting first.
With the speed turned all the way up I'm only getting 80v and 2100RPM. Confusingly enough, when I was powering this motor with the stock G0704 controller I was getting more like 3100RPM.
Since I figure this motor can handle more voltage, I switch to 180v and run it up until I see 130v on the meter. Now I'm getting 3100RPM but escaping from the motor is that one thing which exists in every circuit and that you never want to loose..... smoke.
Tomorrow I'll mess with the trim pots and try to get more speed at the 90v setting, but I'm pretty disappointed. At this rate I could have just stuck with the stock mill controller I think and skipped all the extra hassle. I bought the 225D because I have a 3.8HP motor I was going to use, but it's also rated at 130v (it was damaged in shipping which is why I'm no longer using it). If giving it 130v is going to smoke it then what's the point.
Any ideas on how to proceed?
Re: KBMM-225D and 2.8HP Treadmill Motor
Normally when smoke appears from a DC motor it is due to overload (excess current) which should not have occurred here, only overspeed if exceeding 130v?
Were you using 240vac input for the 180v setting?
The KB PWM version would have been better for a 130v motor as it would have given you the correct voltage from 120vac in.
Also for milling application you get smoother control down to low RPM's.
Al.
Re: KBMM-225D and 2.8HP Treadmill Motor
Yes it is 220vac to get 180vdc. I'll hook up an ammeter and see how much load I'm pulling as the voltage goes up.
Re: KBMM-225D and 2.8HP Treadmill Motor
Also important to use the correct resistor and set the current limit, if needed.
Al.
Re: KBMM-225D and 2.8HP Treadmill Motor
I have the resistor sized per their instructions, and both the motor and drive are rated at 15amps. I would have been less surprised if it overloaded at low RPM while trying to maintain torque, but very little load at high RPM seems like something is wrong. I'll try and troubleshoot it today.
Re: KBMM-225D and 2.8HP Treadmill Motor
I'll take a look at the PWM series but I prefer not to buy another drive if in can avoid it.
Re: KBMM-225D and 2.8HP Treadmill Motor
If the smoke were a case of the motor overheating due to current I would expect to sense it by hot to the touch, although the armature is the part that overheats and takes a while for the heat to filter to the outside case.
Al.