[Newbie] Rockwell Horz./vert. Combo Mill - Wiring W/vfd

CrimsnTide

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I've been reading on here for about as long as I have been looking for a Rockwell 21-122. Well, I finally came across one and I picked it up. Probably paid more than I wanted to, but I'm sure I'll be happy with it once I get set up. With that said, I will start off showing what little I know, so if remarks are to be made, lets get them over with... I'm tough skinned, so you probably won't offend. Being a combo machine, it has TWO motors. The horizontal has a 1 1/2 hp while the vertical head has a 1/2 hp motor. (See Pics) Although the PO had a RPC hooked up in his garage, I think I'm leaning towards a VFD.... My questions are as follows:

I will be utilizing both the horz/vert options with this mill.
Can ONE VFD run both motors since both have different parameters (amps)?
For simplicity, am I looking at two VFD's? Suggestions?
Preferably, I'd like to have one control box (On/Off/Speed)

I'm not sure how much of the electrical is original. When switching to a VFD, how much of it gets bypassed?
Although I'm conceding to hiring someone, it must be the right person. If there are any suggestions, information, links or reads, please let me know. There's a WEALTH of information, I'm just a little overwhelmed with it all.

My apologies - but I am posting this on another forum - so if it looks familiar...

RW_1.jpg

RW_2.jpg

RW_3.jpg


Motor_Horz.jpg

Motor_Vert.jpg

RW_Elec.jpg

RW_Elec_1.jpg

RW_Elec_2.jpg
 
I have a similar setup with a Hardinge UM and have both motors wired to a single VFD.

Most important rule:

Do not put a switch between the VFD and the motor. Shutting off the motor when running with a VFD will damage the VFD. Always use the VFD as the switch.


I am pretty sure it is a bad idea run both motors at the same time, but I don't think that is something you will want to do.

I wired a box with two three phase outlets and plugged the motors into it. I then wired a switch to switch the VFD between outlets. I do not switch between motors when they are running.

The VFD has several programmable terminals so you can wire remote on/off or emergency off switches. You can then wire in a potentiometer to control speed, or use a switch to change between preset speeds.
 
If I'm reading those motor tags correctly one is a 1/2 hp (2.2 amps @220V) and the other 1 1/2 hp (4.8 amps @230V). One of the nice things about VFD's is the provide overload protection. To properly use the same VFD for both motors you will need to reprogram the current differently for each motor. That's a bit of a pain to do each time you switch from one to the other. Personally if it were me I would be looking at 2 VFD's. You can probably use the two existing forward/reverse drum switches but they will be wired to the low voltage control inputs of the VFD rather than to the motors as they are now. . Most of the other electrical stuff will no longer be needed.
 
Just being the hobbyist, I can't imagine having to use both horz./vert. at the sametime, for the same set-up. With the motors being different I was thinking the same - that for both motors to utilize the same VFD, it would have to be "re-programmed" every time the other motor is used. To me, that's a PITA. Now to set-up TWO VFD's, I think I'm getting into the price range of a Rotary Phase Converter (RPC). But to be honest, what attracts me most to the VFD, is not having to change pulley's for RPM adjustment. Not a big deal, but something I would definitely consider. However, like I mentioned above, if I chose to have two VFD's, is there a way to hook up only one "control switch" (On/Off/RPM)
 
I think the only reprogramming you would need to do is for the overload protection.

If you plug the motor into the rotary phase converter, or the wall, you do not have overload protection.

If you are willing to go without overload protection, then I believe you could set up the VFD to run both motors without reprogramming.
 
However, like I mentioned above, if I chose to have two VFD's, is there a way to hook up only one "control switch" (On/Off/RPM)

Yes but it would require either some multiple pin connector that you switch from one to the other or maybe relays and a switch that selects one or the other. In either case it might actually end up costing more than separate controls. I can also see a safety concern with the possibility of forgetting to switch over and turning on the wrong motor.
 
Well, with a fair amount of reading, here's what I wound up doing. I purchased a SECOND VFD to control my Vertical 1/2hp motor. I will mount them both in a large junction box and wire the motors separately. With that being ordered, I do have some questions. I have searched quite a bit and found there are some many DIFFERENT ways to go about this. My ULTIMATE goal is to have one, external control box that would control the VFD that I'm using. I think I'm going to wire each FM50 to have it's own connector - and just plug my external control into whichever axis I'm using.

So here are my questions:
1. Can I (or SHOULD I) shut down the power to the VFD I'm NOT using. In fact, I can see where there will be times I'm not using the mill for months on end. I talked to the "Tech Support" at FactoryMation where I purchased the Teco FM50's. It was SUGGESTED that I could just do a simple switch shutting down the 230v single phase power going to the VFD. Does this sound right???
1a. Does ANYONE think that by shutting down the power, I'm going to lose my settings? I know when it's not running (converting) it won't be using much power. Also, if this is best, I can see wiring up individual

2. I've read where some have wired in a EStop or emergency stop. Is this something I could utilize? Does this shut down the power? Just thinking that I could wire one on the Junction box where both VFD's are housed.

3. My first though was to wire s single twist lock plug coming from the safety switch. From there, I would have two socket/outlets wired in the junction box - one for each VFD. I then would plug into which ever one I need to run. Two things I'm unsure of. Are these able to be "hot-plugged". and also, like 1a above, will the VFD retain their settings when unplugged.

4. I have also thought in not having two connectors - one for each VFD external controls. If I were able to "turn off" the unused VFD, is there a problem if BOTH VFD's were wired in a series? (One wire going from external control to VFD and from there to the same position on the other VFD which is not powered).

I am ELECTRONICALLY inept. I am mentally deficient for the most part when I start reading about contactors, thermal switch, relay 24v. etc etc. etc. I'm feeling pretty good and I'm excited about using the VFD's. I just need what would be the simplist, safest way for me to do this. I don't need an elaborate setup. I'm juts looking for a external control box.

Any help/suggestions or diagrams would be GREATLY appreciated....
 
Congrats on the fine looking milling machine!:drool:
if your are electrically deficient minded, a RPC may be your most easily attained operation of the milling machines functions
that being said, surplus 3 phase vfd's could then be added later on to control the motors, when you feel that you have grasped the electrical concepts better.
 
Doc - I did contemplate HEAVILY on the RPC and when I was thinking of going that route, it really made the most sense. And believe me, if I could have "assembled" one on my own, I probably would have. I watched your tube videos for quite sometime and it did make sense to me. I guess it came down to a time vs. cash issue. I FEEL I can get my mill up and running faster and cheaper with the VFD's. For both Teco's I'm out about $240. I have everything else, J-Box, safety switch, wire, conduit etc. I found a "couple" RPC's on Craigslist, but not knowing anything, the VFD's just made me feel more comfortable in getting this up and running. I'm more broke than anxious, but again, going this route BARELY edged out the RPC.... Thanks for the reply...
 
you are very welcome.
if i can be of any assistance to get your milling machine operational, please don't hesitate to ask.
 
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