Problem- NC400 drives noisy

[jbcj]

Boy when you turn on these drives they whine pretty loud. Is there a way to reduce or stop this. This could almost wake the dead

Jim

[samco]

I think the pwm frequeny of these drives are somewhere around 1khz to 4khz (maybe 10khz I don't remember). Not much you can do abou it. It fall right into the hearing range.

sam

[jbcj]

Thanks I guess I will have to live with it .....Bummer

[machintek]

Schools were especially bothered by the singing of the chokes on the drives.
Bridgeport eventually came out with a different set of chokes for the drives but did not sell a single one. Too expensive.

George

[Hood]

I had exactly the same issue with the NC700 drives on my Beaver Mill so ended up junking them for AC Servos and drives as it was driving me daft and I had only had the mill for a few days.
I got in touch with a guy that knows these drives inside out and he told me of a mod you could do to quieten them down a bit, unfortunately mine already had the mod done, would hate to have heard them before
Not sure if I still have the info and even if I do whether it applies to the NC400's but I will have a look and see when I get home.
Hood

[Hood]

Afraid I can't find the info, must have deleted it when I got rid of the drives.
Hood

[jbcj]

Hood,

Thanks for trying .... It may turn up....
On the up side it may also make my neighbors dogs crazy as well....

Jim