3 phases 6 wires

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He didn't read what was in your article -- he just top-posted without reading so he did not know that it was two separate motors, the power motor and the fan motor. :-)

It could have been a sensible answer for some motors, but that would be with a special VFD. (More common with two wires input and two wires tach output on DC servo motors. :-)

Enjoy, DoN.

I do have servos with lots of wires. Power, Tach, Encoder... And don't get me started on 8 wire stepper motors. Gack!

Nope I never posted that or even measure that... until now... I'm headed out to the shop to find a meter. About zero (+0.1/-0.0).

Are the two sets of wires the same gauge? I'd a thunk the fan would have much small conductors.

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O.K. Almost certainly a thermal switch which opens when the temperature in the motor gets above a certain point. Put it in series with the remote STOP button (if you are using the N.C. stop button and two
momentary contact N.O. FWD and REV buttons). That way, it will shut down the motor if it overheats. (If you are using maintained contact switches for FWD and REV, you'll need to find someplace else to place it so the motor does not start without warning (perhaps while you are checking the machine for what caused it to stop) when the heat gets low enough for the switch to close again. Make sure that if it is opened, you need to do *something* explicit to enable the VFD again when the thermal switch closes.

Good Luck, DoN.

Maybe the idea is that both sets will use the same size wire nuts when being connected up, instead of needing some small wire connectors. :-)

Enjoy, DoN.

Or maybe Leland determined that it was cheaper and easier in terms of time, training, and handling costs to just stock one size of primary wire instead of two... and as an added bonus they had the same benefits with wire nuts. LOL.

I figured it would be good to go into my e-stop circuit. Tells software to shut down all signals instantly. In the event of motor shutdown during a job loss of position will be the least of my worries. Yes position can be lost during an e-stop. There are several ways I can hook up feed hold and e-stop inputs. I think a spindle failure justifies an e-stop.

An e-stop would remove both spindle on and spindle speed signals inputs to the VFD. The cooling fan would continue to operate. I may use it to operated a low trigger relay (have some that only draw 1.2 mills at 12vdc on the trigger input so no risk of arcing on the disconnect) first however so I could install a diagnostic LED to reduce head scratching time.

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You also want it to remove power from everything even if the software has malfunctioned and can't tell things to stop. (E.G, if your controller is based on Windows, and it suffers a BSOD (Blue Screen Of Death), you still want things to stop *now*.

Yes -- a linux based EMC2 could have similar problems -- though usually from component failure, not the software hangup of Window fame. :-)

Depends on how it is being done. If steppers, certainly you lose position during an e-stop. If servos, some interface cards offer the option of a battery backup to the position memory, and a counter which is battery backed up to catch any position changes (e.g. overshoot) when the power fails. Then it is a SMOP (Simple Matter Of Programming) to recover from that -- if it matters.

Certainly so. You don't want the axes to keep feeding against a stopped cutter. *Plink*!!! :-)

Good -- and also to the axis servos, I would hope.

Sounds good.

Good Luck, DoN.

I haven't seen a BSOD in over 10 years. XP is a lot better than

95/98/98Se/ME ever were. I don't even bother to use Tweek UI to change it to a RSOD (Red Screen Of Death), anymore. :)

And, that is what your charge pump is for if it does.

Charge pump? You're WAY out of date! DDS is the way to go, these days. PLL is OLD technology.

ROFL. I am retrofitting a 1982 Hurco to Mach 3 control. Of course I am out of date. LOL.