10ee VFD mounting

I put my VFD in the access panel right below the lathe apron. IIRC, that's where the MG sat. its been over 10 years.

I put a pot on the original speed dial for speed control. And took three wires from the forward/off/reverse rocker bar to the VFD for on/off/reverse control. That way, my machine uses all the original controls.

You'll LOVE a 10EE with new speed control. I used a 5 hp. motor and kept the old backgear. If I were to do it over I'd go with a 10 horse and sell the backgear on eBay. Which way are you going?

Karl

I was going to use a pot on the speed control and the original FWD/REV/ OFF switch. Mine has 5 wires coming off from it, but for the life of me, can't figure out what two of them are for. The three black wires are the FWD/REV, DP contact set. There are two yellow wires that I am not sure.

I have a 7.5 hp on the VFD for now. It seems to have pretty good torque all the way down to almost stalled (

O.K. What kind of switch is it?

If a "drum" switch, with a lever moving from "REV" to "OFF" to "FWD", and a three phase motor, you should expect three wires in, and three wires out and the switch (with line three phase, not with the VFD) goes between the line and the motor. One line is simply set up for "CONNECT/OPEN/CONNECT", while the other pair are set up to be straight through in forward, and swapped in reverse. But this is six wires. And you can use one of thet swapped input wires as the COMMON for the VFD and the two swapped motor phase wires to go to the FORWARD and REVERSE control points on the VFD.

However -- if there were big contactors to switch the motor from FORWARD to REVERSE, and you have a set of pushbuttons (in whatever order) you can expect A common between the two FORWARD and REVERSE pushbuttons, and a separate FORWARD and REVESE wire from NO (Normally Open) contacts, and another pair of wires for the STOP pushbutton, which will be NC (Normally Closed). The VFD should be capable of being wired to use this arrangement too. Just read the manual.

O.K. As long as the fan does not die. :-)

Good Luck, DoN.

I'm not sure what sort of switch it is. It's integral to the casting, and I have not found a way to remove it to review the actual contacts. The two extra wires don't seem to ohm out to anything useful that I can find. For all I know they don't go anywhere. The three I have identified will work quite well for the FWD/REV function on the VFD.

Yes, very true. And a good reason to keep the backgear so the motor speed can be kept up a little bit, while dropping spindle speed to nearly stall.

It does have a thermal protect, so if the fan did die the drive would eventually shut itself down. I could add an additional fan easily enough. For that matter, perhaps an inverse speed sensitive fan for the motor too. Shouldn't be too hard with some sort of comparator circuit...

Anyhow. Thanks for the input guys.

JW

O.K. Is there a lever which you move from REVERSE to STOP to FORWARD (common with a drum switch), or are there three pushbuttons (FORWARD, REVERSE, and STOP in whatever order the maker though made sense)? The latter format is normally used for controlling contactors (heavy duty relays), while the drum switch normally switches the high current to the motor directly -- at least in the original system. Since this is a Monarch 10EE, (I had missed that before), it is likely the latter since it is controlling a DC motor, not a three phase one, though it might still *look* like a drum switch with the lever.

Aha -- I think that I've found an illustration which shows the switch. A lever near the spindle and just a little below it.

O.K. Are the other two connected together *except* when you press the STOP button?

Never mind -- not a button. But are the black wires connected together except when the FORWARD/STOP/REVERSE lever is in the STOP position? If so, then they can be used for the stop function to the VFD, and the momentary start ones from the others. Or -- as long as the FORWARD and REVERSE wires hold connection to common as long as the lever is in the corresponding position, you can simply put some wire nuts on the black wires and tuck them away somewhere.

Good Luck, DoN.

They could be the leads to the worklight. On my 1961 10EE I believe the leads to the light are run with the fwd/rev switch wires. If your light is gone, and most are, there's a small round cast cover on the back of the headstock in line with the spindle switch. That not only serves as the mount for the light and a toggle switch, but I think also gives access to the back of the spindle switch.

Could be. There is such a cover. I cannot get that out either Pretty much same reason as above for the switch. I removed the screws and pried on it gently with a screwdriver but nothing seemed to budge. Several layers of paint. Someday I will get around to stripping it and giving it a "pretty" paint job.

And for DoN, yes I think it is the latter. The wire gauge is much to light to be controlling the motor current directly. The leads ran to the DC "control" box in the end casting. Assumably to control switching relays and whatnot.

It does maintain contact when in the appropriate position(center to FWD, and center to REV)

Thanks

JW