So I have repairs and repaint pretty much completed on my 2HL, and made my first cuts with the universal head...and all was well at around 4-500 RPM, then tried some light cuts around 1000...and popped the overloads a couple of times! So started trying to diagnose. I am NOT a whiz with motor wiring, but have some limited knowledge. Here's the background...had to buy a motor controller (used, but serviceable)and heaters sized for the 3HP Westinghouse motor. My first thought was maybe motor was wired for 440...I'm running 240. Clamp on ammeter on leads showed 10amps( I think I only checked two leads)...motor nameplate showing 8 amp (I assume plate is showing the FLA??) So pulled motor out, but before disconnecting, tested voltage on all three motor leads, and did another amp check, with no load. And this is where I start getting lost! With no load, my readings (T1, T2 T3) was 5-3/4, 1/4!!! and 5-3/4. Actually, my first check I didn't see the needle move on T2 as I was still on a 15A range...so I thought I had motor issue! I pulled connections (it WAS wired correctly for low voltage)
I then ohm checked leads (after some research on how) and could NOT find a problem. So hooked it all back up and started double checking things starting with RPC...I am running a pony start 15hp, but UNBALANCED. I realize this can be an issue if the RPC sizing is marginal, but did not think this would be a reason for the low reading on one lead??? I don't understand why one leg is SO much different than the others on current draw! Can anyone explain?
Here are some numbers...
RPC line voltages (individual, one lead of multimeter grounded), L1 118v, L2 172v, L3 120v
Voltages measured lead to lead...L1,L2=205v
L2,L3=213v, L1,L3=237v
(L2 is the generated leg)
Ohms on motor leads, 1-4,2-5, and 3-6 all around 1.4.On7-8,8-9,7-9 around 2.4. No shorts to ground.
After hooking it all back up, did a couple more amp checks. First with no load. And I swapped T2,T3 motor leads and tried it (direction reversed of course, but belts off) and the low amp reading was still on the center terminal of controller. Then wired and set it all up and ran under loads...(just powering head, no cuts) At 412RPM, got 6, 2.5, and 8amps. T2 still LOW. At 1085RPM, got 10, 5 and 12.5!
I pulled one side of universal head apart for some mounting/casting repairs (have another thread going on that one) and found a black grease...seemed a little thick, and I am planning on a total clean out and re-lube soon, maybe Corn head grease? (Have read several threads saying oil as originally called for leaks out badly)
Do you guys think this grease in the Universal head could be the reason for the high current draws at higher RPM's? Or do I have other issues? Is the low, low draw on one lead due to the RPC imbalance and if so, is it necessary to add some capacitors to try and balance better?
I would sure appreciate some advice and opinions!
Charles
I then ohm checked leads (after some research on how) and could NOT find a problem. So hooked it all back up and started double checking things starting with RPC...I am running a pony start 15hp, but UNBALANCED. I realize this can be an issue if the RPC sizing is marginal, but did not think this would be a reason for the low reading on one lead??? I don't understand why one leg is SO much different than the others on current draw! Can anyone explain?
Here are some numbers...
RPC line voltages (individual, one lead of multimeter grounded), L1 118v, L2 172v, L3 120v
Voltages measured lead to lead...L1,L2=205v
L2,L3=213v, L1,L3=237v
(L2 is the generated leg)
Ohms on motor leads, 1-4,2-5, and 3-6 all around 1.4.On7-8,8-9,7-9 around 2.4. No shorts to ground.
After hooking it all back up, did a couple more amp checks. First with no load. And I swapped T2,T3 motor leads and tried it (direction reversed of course, but belts off) and the low amp reading was still on the center terminal of controller. Then wired and set it all up and ran under loads...(just powering head, no cuts) At 412RPM, got 6, 2.5, and 8amps. T2 still LOW. At 1085RPM, got 10, 5 and 12.5!
I pulled one side of universal head apart for some mounting/casting repairs (have another thread going on that one) and found a black grease...seemed a little thick, and I am planning on a total clean out and re-lube soon, maybe Corn head grease? (Have read several threads saying oil as originally called for leaks out badly)
Do you guys think this grease in the Universal head could be the reason for the high current draws at higher RPM's? Or do I have other issues? Is the low, low draw on one lead due to the RPC imbalance and if so, is it necessary to add some capacitors to try and balance better?
I would sure appreciate some advice and opinions!
Charles