Need Help!- DC Motor info

[ozzie34231]

Hope this is the place for this question.
I have a 2HP DC motor. The nameplate is shown in the picture. I'm curious about the meaning of the MSS entry. What does that mean?
I also have a KB controller for it, KBRG 225D. I know the controller will put out more than 180V, probably enough to attain 2500 RPM. Does the MSS mean that I can over speed this motor even more?

My intended use is for the head of an IH mill. I bought an IH mill without the head and am intending to build a head from scratch, I do have the IH Z saddle.
I have a Hurco Quill which I'll mount in a static saddle consisting of a couple pieces that look like auto connecting rod bottoms.

What I'm struggling with at the moment is the motor mount, speeds and pulley system. I want spindle speeds from 4000, (max for the Hurco), down to 200 RPM for surfacing with a large fly cutter, maybe HSS.
I do have a set of variable pulleys that can handle the HP but they are large, eight inches dia. They would give a 400-500% range.

All thoughts appreciated.

Ozzie

[JonLed]

Maximum Safe Speed?

Jon

[Al_The_Man]

5500rpm is high for a DC motor, so I would think definitely it stands for Max Speed.
The drive you have are four quadrant SCR drives and the manual states output 180vdc on 240vac input.
Al.

[ozzie34231]

Okay, let's say it stands for max spindle speed, or max safe speed; does that imply that if I could feed it 500+VDC it would attain those speeds? (Without burning up)
What other circumstances are implied; how else does it reach high RPM?

Ozzie

[Al_The_Man]

Originally Posted by ozzie34231 What other circumstances are implied; how else does it reach high RPM? Ozzie

Max RPM is relative to applied voltage.
On a spindle, it is advantageous to have Tach feedback for accurate speed control.
Al.

[ozzie34231]

What's going on here?
Is someone sitting in for Al?
Ozzie

[Al_The_Man]

Whats up?
Need a bit more info?
You can most likely operated at higher than the rated RPM, but most likely you will shorten the life of the motor, something I would not recommended on a regular or permanent basis.
Al.

[der_fisherman]

If the DC motor has wound fields (no "Cogging when turning by hand), probably a shunt wound or compound DC motor, then theoretically you could bring the field coil connections outside, seperate them from the commutator connections and electronically reduce the voltage to the fields, which if my memory serves me correctly, allow the motor to turn faster......leave the connection and voltage to the commutator the same, eg, a higher voltage is not required for this effect.

What effect that will have though on the life of the motor in the long run, I could not say.....but do let us know please!

Also, do not "over do it" as it could fly apart and seriously hurt anyone standing nearby....

[ozzie34231]

Thanks for your effort Fisherman.
The nameplate clearly indicates a PM field.

From my experience with Al the Man, I continue to believe he is not replying. The answers are not responsive to the questions, not at all like Al!

Let's just drop it; I'll stumble along on my own.

Ozzie

[der_fisherman]

You wrote "The nameplate clearly indicates a PM field", what did you mean? I live in Germany and my English has seriously deteriated over the last 30 years or so!!!
Thanks in advance
Der Fisherman

[Al_The_Man]

Permanent-Magnet Field.
Al.

[der_fisherman]

So simple, many thanks, I thought you were referring to my "Nickname"!!
regards
Der Fisherman