Replacement Lathe

The 10EE was a DC motor, so it cannot be hooked up to a VFD and run. If the original motor and electronics are all intact and functional, the machine can be run off of single phase using L1 and L3, L2 is not used to run the lathe itself. That is a big if for all the electrics and mechanicals to be there and working. A VFD conversion is no simple task, it is expensive, and as mentioned by others you would be better off using the lathe reduction gear for low speeds.
 
According to the manual the primary motor is ac which is connected to the dc generator, all of which are still there intact. The plate on the ac 3 phase motor says it is 3 phase, and I believe the coolant pump is 3 phase as well. All the VFD will do is supply 3 phase to the ac motor. All the other parts are there for the rest of the functions. It is still unknown of all the motors are good. I won't know that until I get power to the Ac motor. You can see the AC motor in the last pics top left and the dc in the top right pic.
 
Here is the manual I have for the lathe.
 

Attachments

  • Mopnarch Manual.pdf
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Chris,

The motor/generator (MG) is there, under the chip pan. I can't see the exciter, which sits on top of the MG, under the tailstock. You have a coolant pump; that's not a good thing, IMHO, since machines with coolant tend to have more issues due to corrosion from coolant. It looks like the DC spindle motor is there as well. I would need to see what's behind the cover on the headstock end to see if the DC control panel is there, etc.. A photo or two looking behind the cover on the tailstock end will tell us about the exciter. Get photos of the commutators of the generator, exciter and spindle motor.

The main AC contactor is behind the cover on the back of the machine, below the headstock and behind the QC gearbox. I would like to see what's in there.

The MG wants to run at constant speed, so there's no advantage to a VFD to power it and 5HP VFDs that can put out 230 VAC 3-phase are expensive. You can run it with a rotary phase converter (RPC) or "static converter" for a lot less money than a VFD.

What's the serial number? (It's on the plate in the second photo, but I can't make it out.)

A lot of covers are off. Are they around, or missing?

One interesting feature of the machine is the ELSR (Electric Leadscrew Reverse) option. Yours seems to be fairly complete, which is unusual for round-dials. (This model 10EE is called a "round-dial" because of the shape of the selector plate on the quick change gearbox; later machines have a square plate and are called "square-dials.)

Overall, the odds appear to be in your favor that the original drive is still there. If so, it can probably be made to run again without too much drama. I know quite a bit about this drive system and will be able to help you with that.
 
Cal Haines said:
Chris,

The motor/generator (MG) is there, under the chip pan. I can't see the exciter, which sits on top of the MG, under the tailstock. You have a coolant pump; that's not a good thing, IMHO, since machines with coolant tend to have more issues due to corrosion from coolant. It looks like the DC spindle motor is there as well. I would need to see what's behind the cover on the headstock end to see if the DC control panel is there, etc.. A photo or two looking behind the cover on the tailstock end will tell us about the exciter. Get photos of the commutators of the generator, exciter and spindle motor.

The main AC contactor is behind the cover on the back of the machine, below the headstock and behind the QC gearbox. I would like to see what's in there.

The MG wants to run at constant speed, so there's no advantage to a VFD to power it and 5HP VFDs that can put out 230 VAC 3-phase are expensive. You can run it with a rotary phase converter (RPC) or "static converter" for a lot less money than a VFD.

What's the serial number? (It's on the plate in the second photo, but I can't make it out.)

A lot of covers are off. Are they around, or missing?

One interesting feature of the machine is the ELSR (Electric Leadscrew Reverse) option. Yours seems to be fairly complete, which is unusual for round-dials. (This model 10EE is called a "round-dial" because of the shape of the selector plate on the quick change gearbox; later machines have a square plate and are called "square-dials.)

Overall, the odds appear to be in your favor that the original drive is still there. If so, it can probably be made to run again without too much drama. I know quite a bit about this drive system and will be able to help you with that.
Click to expand...

I will get the pics tomorrow. All the covers are there, just not installed. I will get the serial number tomorrow too. The VFD I was going to get was not so much for this lathe, but so I could use the VFD for other 3 phase equipment in the future. In my shop I am the only one to run things so I could just switch the VFD to any other 3 phase stuff I may get in the future. I may just go with the static converter for cost reasons. Thanks for the offer to help as this 3 phase stuff is all new to me.
 
Cal Haines said:
Chris,

The motor/generator (MG) is there, under the chip pan. I can't see the exciter, which sits on top of the MG, under the tailstock. You have a coolant pump; that's not a good thing, IMHO, since machines with coolant tend to have more issues due to corrosion from coolant. It looks like the DC spindle motor is there as well. I would need to see what's behind the cover on the headstock end to see if the DC control panel is there, etc.. A photo or two looking behind the cover on the tailstock end will tell us about the exciter. Get photos of the commutators of the generator, exciter and spindle motor.

The main AC contactor is behind the cover on the back of the machine, below the headstock and behind the QC gearbox. I would like to see what's in there.

The MG wants to run at constant speed, so there's no advantage to a VFD to power it and 5HP VFDs that can put out 230 VAC 3-phase are expensive. You can run it with a rotary phase converter (RPC) or "static converter" for a lot less money than a VFD.

What's the serial number? (It's on the plate in the second photo, but I can't make it out.)

A lot of covers are off. Are they around, or missing?

One interesting feature of the machine is the ELSR (Electric Leadscrew Reverse) option. Yours seems to be fairly complete, which is unusual for round-dials. (This model 10EE is called a "round-dial" because of the shape of the selector plate on the quick change gearbox; later machines have a square plate and are called "square-dials.)

Overall, the odds appear to be in your favor that the original drive is still there. If so, it can probably be made to run again without too much drama. I know quite a bit about this drive system and will be able to help you with that.
Click to expand...

Here are the pics of the motor generator and a better pic of the data plate. The manufacturer number is 722. I'm guessing that is the serial number? Also included a pic of all the parts that come with it. The last pic is one part I am not sure as to what it is.

SAM_1117.JPG

SAM_1118.JPG

SAM_1120.JPG

SAM_1114.JPG

SAM_1115.JPG

SAM_1121.JPG

SAM_1122.JPG
 
I am not familiar with the older Monarch AC motor generator machines, just the newer versions without the AC motor generator. I was able to pull up a simplistic wiring diagram on this version. I think you would be best off with a RPC, the static converters one needs to derate the AC motor generator drive. A VFD does not like different loads switched in and out which can damage them under load, and the VFD settings are usually machine/motor specific. I have no idea how it would be setup to work in this type of motor generator control system.

Monarch 10EE Motor Generator Schematic.jpg
 
A motor generator EE will run fine on a 4-8 HP heavy duty Static Converter. I have seen it done with Phase a matic converter. Not ideal but for a few hundred you are up and running. Downside of MG machines is they are loud, you essentially have 3 motors running, the AC, the exciter and the DC. Throw in a rotary converter and now you have 4 motors. A later model with tube drive would be my preference, owned one for over a decade now.
 
milomilo said:
Here are the pics of the motor generator and a better pic of the data plate. The manufacturer number is 722. I'm guessing that is the serial number? Also included a pic of all the parts that come with it. The last pic is one part I am not sure as to what it is.
Click to expand...
Yes, manufacturer number is the serial number. Part of the serial number is missing. It should be 5 digits for that machine. Look on the right end of the bed, between the tailstock flat way and the front Vee way, it's stamped there.

The belt-driven exciter is in place and appears to be connected. That's good.

You have a vintage Monarch follower rest; nice. The steady rest isn't a 10EE steady; it looks like someone made an adapter to get it to the right height. For no more often than you need one, it will work find.

It you have more than one 3-phase machine, your best bet is to go for a rotary phase converter (RPC). If you get a so called "static phase converter" (SPC), you can use it to make an RPC by just adding an idler motor and some run caps, so I would start there if I was on a budget. I know of several 10EEs running from SPCs.

I agree with mkjs that trying to use a VFD to drive multiple machines, even one at a time, is a bad idea.

A SPC is nothing more than a motor starter, that is, a relay and a starting capacitor (or two). It functions by connecting the starting capacitor(s) to the third phase during startup, much the same way that a capacitor-start single-phase motor is started. Better SPCs include run capacitors to continue to power the third phase after the starting caps kick out, directing current from the other two sets of windings into the third set of windings, as the phase of the voltage changes. An RPC is just a SPC with an idler motor (any 3-phase motor will work, 7.5HP being a good size for a 10EE). The idler motor acts as a mechanical capacitor, providing current for the third phase of the load machine. Correctly balanced, an RPC can provide fairly well balanced 3-phase voltage to a machine.

WNY Supply has a static converter for $75 with free shipping: http://phaseconverterusa.com/3--5-HP-HD-SCX-Static-Phase-Converter-_p_33.html
WNY used to have a their own webpage with a lot more products; it looks like they are now being sold through phaseconverterusa. I don't know if this converter includes run capacitors or not. If not, I would add two run caps to help balance the third phase. Some 10EE owners have reported issues with static converters when rapidly reversing the spindle and I believe that the lack of run caps is a explanation for that problem.

The photo of the commutator is that of the generator. It looks very dirty. I would remove the brushes and clean all the three commutators with a toothbrush and solvent (letting the solvent dry overnight) before trying to run the machine. You may need to replace the exciter's belt if it's been sitting a long time.

I still need to see what's under the cover on the headstock end. Take photos of the insides of the DC Control Panel, the large box to the right of the DC motor, and the big rheostats above it.

Would it be possible for you to upload higher resolution photos, or put them on something like DropBox or PhotoBucket?
 
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