I have a Moak 32" band saw from 1949 with a Master Motor (3hp/3ph - 575rpm,13.7 amp) I am using a Yaskawa 19.5 amp output VFD to run the motor (230 single phase in) . I was concerned about the age of the motor and the rep recommended a noise filter, the Tonkin-L350 .
I have only used the saw 2 or 3 times and everything was fine. Well I am in the process of completing a restoration on her and I took of the rubber tires and wanted to clean off all the old glue. I ran the VFD at 3 for the frequency to run it slow so I could scrape all the gue off with a steel chisel.
I noticed this funny electrical smell, couldn't figure out were it was coming from then I put my hand on the Tonkin and nearly burned my hand. There was some clear liquid coming out of the top, very little,a few drips so I imediatly shut it off.
Mu question is, why would it heat up like that and do I really need the Tonkin -L350 noise filter? I took it off the machine and ran it directly from the VFD to the Master motor with no issues running it at 3f but I only ran it for a few miniuts but the motor was still cold, not even warm.....
Is it really necessary to have this filter in there? I was just concerned because of the age of the motor.


Any thoughts about this, what exactly is the L350 doing to heat up like that and what was the clear liquid coming out? Do I really need the filter?


Thank you,

Brian