- Joined
- Jun 8, 2016
- Messages
- 603
Hi Investigator,
(all dependent on load and service voltage!!!)
Answer:1- you will have 2 different capacitor values when balancing a RPC.
phases A and B will be supplied voltage (for this purpose) their running voltage is 240vac between poles
phases A and C will have one supplied leg and one generated leg, their running voltage may be as low as 200vac between poles
phases B and C will have a generated leg and a supplied leg, their running voltage may be around 226vac between poles
if you were to treat phases A-C, exactly like Phases B-C, you would throw the motor back out of balance by application of too much capacitance on the B-C phase that may only require 30 or 40 mF of balancing capacitance.
phases A-C in this scenario would require the most capacitance maybe as much as 80 or 100 mF (all dependent on load and service voltage and rotation!!!)
.
Well, got everything wired up and running. I didnt put any run caps in, only using the idler motor. I turned it on and took some readings with my meter, hopefully folks can tell me if and what I need to do to make improvements.
With just the idler on, and no other motors i have:
ground/com -L1 123Vac
Grnd/com-L2 124Vac
Grnd/com- L3 170Vac
L1-L2 249V
L1-L3 220V
L2- L3 208V
When I turned on the lathe (Logan 12") and took readings at slowest and fastest speed, the readings between l1-l3 and l2-l3 were the same as without the lathe on.