This has been discussed somewhat in another thread, but wanted this to be its own topic so hopefully I can understand this better.... other thread - https://sawmillcreek.org/showthread....per-Wadkin-BEM
I just got this shaper (Wadkin BEM) and am trying to trouble shoot why it won’t start properly on the Rotary Phase Converter. Trying to isolate if the RPC is simply undersized or if it’s currently wired for high voltage. Currently, the shaper motor will start but then trip the contactor overload after 2-3 seconds before getting up to full speed. Removing the drive belt (that connects the motor to the spindle rotation) allows the motor to start and run fine (it seems), which has me concerned. Motor is 12 hp / 27.4 FLA @ 230v and my Kay converter is rated to start a 10 hp Max single motor. I spoke with Kay support and he suggested I confirm the motor voltage wiring first before assessing a few different options that could be added to the RPC to help with the large startup current needed.
Photos attached that show the motor wiring schematic that was inside the junction box on the motor where the 12 motor leads and incoming lines connect. Currently there are (3) line wires coming in from the control/switch/incoming power source and (4) motor leads connected to each line wire. Each set of 4 leads + 1 line is stacked together on a short bolt and tightened with a nut on the end and wrapped in electrical tape.
The way the motor is currently wired as I received the machine is shown (written out) in another photo and does not match either of the diagrams shown on the schematic, neither high or low voltage. I am confused. Why would it be wired differently than what it shown?
I do not have experience in this part of electrical work and do not know how to interpret this diagram. What do the squiggly lines mean compared to the straight lines? I have tried looking this up online and have not come across anything that explains how to interpret this.
The shaper is new to me, but I saw video from the previous owner of the machine running what seemed to be properly just before I bought it and they said they thought it was 240v (metered 3 phase) and it had a 250v plug on it, but you can never assume anything completely just from existing conditions.
Should I re-wire the motor leads as shown on the paper diagram for low voltage and test? What is the risk / harm in doing this?
Thanks for any help!
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