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New to me RF 45 ..... In the shop

Is there a book ? VFD's for dummies ?

I have questions .............

In my shop , there is one 208 v wall outlet , fed from a double pole 20 amp breaker in the panel , What ever machine I happen to be running gets plugged in , I only run one thing at a time .
I have a 12 x 36 lathe , another mill & two welding machines that share the same wall outlet .

This brings up the first question ...........
A VFD requires programing ? , I'm making assumptions here but the VFD will need some parameters set ? , or not ?? .

This machine is going to be plugged in only when I'm using it ............
Will the saved settings that get programed into the VFD be lost when it is unplugged ? .

Next question ..........
I would like to retain the use of the switches on the front panel of the mill , is that possible ? . I should mention , in a box on the back of the machine , there's a transformer that steps 208 down to 24 volts for the control circuit , it almost looks like this is an ad on that was done after the machine was built . I do not have a wiring diagram for this machine and I'm not sure it is original , unmolested or butchered .
 
Gearhead88 said:
Is there a book ? VFD's for dummies ?

I have questions .............

In my shop , there is one 208 v wall outlet , fed from a double pole 20 amp breaker in the panel , What ever machine I happen to be running gets plugged in , I only run one thing at a time .
I have a 12 x 36 lathe , another mill & two welding machines that share the same wall outlet .

This brings up the first question ...........
A VFD requires programing ? , I'm making assumptions here but the VFD will need some parameters set ? , or not ?? .

This machine is going to be plugged in only when I'm using it ............
Will the saved settings that get programed into the VFD be lost when it is unplugged ? .

Next question ..........
I would like to retain the use of the switches on the front panel of the mill , is that possible ? . I should mention , in a box on the back of the machine , there's a transformer that steps 208 down to 24 volts for the control circuit , it almost looks like this is an ad on that was done after the machine was built . I do not have a wiring diagram for this machine and I'm not sure it is original , unmolested or butchered .
Click to expand...
An rpc would be plug and play. For a vfd youd have to wire the forward, reverse, start and estop into the vfd.
The vfd vs rpc holy war is as old as time :P
Yes there are parameters and settings. Yes they keep across power outages.

Theres alot of electronics buffs around here that would love to guide you through it. Its not that difficult and when your setup and done youre done... get a cheap vfd and sometimes your settings might get lost randomly.

I think the forums needs a vfd manufacturer sponsorship

This post has been brought to you by Westinghouse
 
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Y
Gearhead88 said:
Is there a book ? VFD's for dummies ?

I have questions .............

In my shop , there is one 208 v wall outlet , fed from a double pole 20 amp breaker in the panel , What ever machine I happen to be running gets plugged in , I only run one thing at a time .
I have a 12 x 36 lathe , another mill & two welding machines that share the same wall outlet .

This brings up the first question ...........
A VFD requires programing ? , I'm making assumptions here but the VFD will need some parameters set ? , or not ?? .

This machine is going to be plugged in only when I'm using it ............
Will the saved settings that get programed into the VFD be lost when it is unplugged ? .

Next question ..........
I would like to retain the use of the switches on the front panel of the mill , is that possible ? . I should mention , in a box on the back of the machine , there's a transformer that steps 208 down to 24 volts for the control circuit , it almost looks like this is an ad on that was done after the machine was built . I do not have a wiring diagram for this machine and I'm not sure it is original , unmolested or butchered .
Click to expand...
Yes a VFD requires programming. There is a short list of things that you have to program. Motor voltage, Max current, spin up time etc. Then are things you can program if you want to if you feel the need to tweak something later. The VFD will retain the parameters regardless of whether it is hooked up to power or not. You should be able to use the electric switches on the front of your mill, I did so on my lathe.
 
I ran rotary phase converters for 20 years with no issues. I have 3 phase power now, but recently got a VFD for my mill. I love the VFD.
 
quitereal said:
The vfd vs rpc holy war is as old as time
Click to expand...

Ain't that the truth!

My church is the VFD.

I think the two discerning features are:

Rotary converter - you only need one for lots of machines.

VFD - you get continuously variable speeds.

After that the water gets muddy with a kaleidoscope of colours and patterns. Pick your poison.

As a VFD fan, I can list many advantages and disadvantages.

1. includes all the protection relays normally required for metal working machines.

2. provides variable speed adjustment control of a 3ph motor.

3. Most VFDs include sector less vector control (SLV) of power output to match power to changing motor needs. The result is incredibly smooth motor operation

4. Live direction reversing.

5. Programmable acceleration and deceleration.

6. Programmable frequency limits.

7. Low voltage control of all functions.

8. Full fault protection.

9. Voltage and current matching to the motor.

10. Various input and output controls for associated motor control systems.

Others have already spoken to the programming requirements. I don't disagree with anything that has been said.

I can't really speak to the advantages of a rotary phase converter beyond what has already been said. If someone wants to, they could write a similar list of advantages for an RPC.
 
At the now closed down mill I worked at, our speed adjustment ran the gauntlet from variable pitch sheaves to DC motors to VFDs. A couple of machines were converted from VPS to VFD. The maintenance foreman was overjoyed at the conversion. VPS are very high maintenance. Changing out a Reeves drive would be a given. They are more problematic than even a VPS.
 
Like everything in the world of electronics these days, it can be as simple or as complex as one wants to make it.

The Hydmech saw I just got, is 575v three phase. So is a surface grinder that I have. In both cases, easy/quick on and off doesn’t matter much to me. So I have a 240V single phase feed, into a step up transformer that gives me about 600V single phase. That then goes through a 3hp rated AC drive, which acts like a VFD. Even though it is a ‘3 phase’ unit, upsizing it and only feeding it single phase works, because of how the innards of the drive work. This part of things is a bit of a black magic to me, I just know the guys I spoke with explained that the drives will work that way, and they do.

At this point for either unit it’s wired direct to the motor, and stop/start is done by the buttons on the front of the starter.
 
Another option not mentioned is a phase perfect converter. It will change single phase AC to correct 3 phase. By correct I mean the third leg is fully there not just there as voltage like on the cheap converters. They are available up to 20 horsepower capability last time I checked. They would be the most expensive option short of putting in actual 3 phase power.
 
We payed $10,000 for ours which was a bit overkill then another $600. For their surge protector.
They work great though ours is for the bigger motors so don’t S*it you pants about what we paid.
 
I had an RF45 some years ago, a 1998 King, Taiwan model. I briefly looked into VFD conversion based on some guys converting theirs to CNC & of course retrofitting with 3-phase motor. One thing to inquire about is the motor itself. Things may have improved on that front but I recall finding lots of motor candidates matching the HP requirements & close enough flange dimensions, but there were some variations to the shaft length/diameter/key (something else I can't recall) which would require a bit of adaptation work. It wasn't quite plug & play. Having said this, RF-45 really means a 'style' IMO. There can be differences between two RF-45's between the same manufacturer spaced apart 5 years. So possibly you really wouldn't know what you have without pulling the motor unless you had some definitive manufacturer data. Some guys ho were lucky & had a Grizzly for example just ordered the 3P motor directly from them because it was available as an option. I remember calling Modern tool back in the day, they sell a Chinese RF-45 & 3p motor was available as a delivery item. Presumably the VFD would play nice with it but I've never done a conversion or setup so would refer to much smarter guys here. Anyways, I think your 220V 20A would be plenty to feed the VFD.

1735366967681.png


In terms of the other electrics, I'm curious what you have that would require the 24v but wouldn't be bypassed with VFD. Your 220V motor would have start/run capacitors & centrifugal switch, that stuff goes bye-bye with 3P & VFD. My RF45 electrics were pretty basic. Basically light on with power & e-stop. No pump or anything else. As mentioned, yours may well be different. The DRO & power feed were all wall outlet 110V, separate circuit. I'm told by my VFD mentors that mills are <cough> 'easy'. Lathes... kind of depends on their other features.

1735367610505.png
 
PeterT said:
I had an RF45 some years ago, a 1998 King, Taiwan model. I briefly looked into VFD conversion based on some guys converting theirs to CNC & of course retrofitting with 3-phase motor. One thing to inquire about is the motor itself. Things may have improved on that front but I recall finding lots of motor candidates matching the HP requirements & close enough flange dimensions, but there were some variations to the shaft length/diameter/key (something else I can't recall) which would require a bit of adaptation work. It wasn't quite plug & play. Having said this, RF-45 really means a 'style' IMO. There can be differences between two RF-45's between the same manufacturer spaced apart 5 years. So possibly you really wouldn't know what you have without pulling the motor unless you had some definitive manufacturer data. Some guys ho were lucky & had a Grizzly for example just ordered the 3P motor directly from them because it was available as an option. I remember calling Modern tool back in the day, they sell a Chinese RF-45 & 3p motor was available as a delivery item. Presumably the VFD would play nice with it but I've never done a conversion or setup so would refer to much smarter guys here. Anyways, I think your 220V 20A would be plenty to feed the VFD.

View attachment 56766

In terms of the other electrics, I'm curious what you have that would require the 24v but wouldn't be bypassed with VFD. Your 220V motor would have start/run capacitors & centrifugal switch, that stuff goes bye-bye with 3P & VFD. My RF45 electrics were pretty basic. Basically light on with power & e-stop. No pump or anything else. As mentioned, yours may well be different. The DRO & power feed were all wall outlet 110V, separate circuit. I'm told by my VFD mentors that mills are <cough> 'easy'. Lathes... kind of depends on their other features.

View attachment 56767
Click to expand...

Thank's Peter

I'm not in a hurry to get this going , I have another mill I use often , I'm shooting for .... sometime before summer .

For the time being it is a coat rack / storage shelf .

The only thing I've done to this mill since it arrived was to clean it and get all the 110 volt stuff working , I added a quad outlet box , so the DRO , the power feed and a work light can be plugged in , with room for one more item to be plugged in . There was a coolant pump but it is fubared and was a victim of being put away wet , the reservoir that once held the coolant is missing but the ruined pump was still there . Maybe down the road I will replace it and that will be the fourth thing that gets plugged in to the receptacle box.
The receptacle box has it's own cord and plugs into a standard wall outlet.

Just to review .............. it has a three phase motor , I believe it came this way .
The 208 / 24 volt transformer ? , at this point I'm not sure about that , it sure looks like it was added on at some point .
The transformer is inside a box that is mounted externally , on a removable cover that is screwed to the back of the column . Inside the column , when you remove the cover there looks to be a large capacitor ? , I'm not sure , I'll get some pictures of that when I get a chance .

At this point , it's a mystery machine ............... I should make up a wiring diagram of the way it is configured right now ................... I've been staying busy with other stuff .

I'm the second owner , it came from House of Tools 1994 ish ..........


The transformer ..........

IMG_5373.JPG

The motor

IMG_5143.JPG

CASF8480.JPEG
 
Yesterday I pulled my blast cabinet out of the way so I could get at the back of the mill and peek inside the cover on the back of the column .

Now I know what the 208v - 24v transformer is for .

IMG_5432.JPG




IMG_5433.JPG



IMG_5429.JPG
This is the cable that supplied the machine in it's former location .


I feel the need to mention ..... Some guys are in a hurry to reply without reading the whole post.

So

If you are reading along up to this point ................


A VFD ?

I'm not convinced that is what I want , leaning more towards leaving the controls and wiring in the machine original , not rewiring the machine , avoiding complexity and additional controls .

It's a gear drive .......... I'm good with that .

I will mention this again because no one has responded to post # 4 , where I posted a picture of a digital phase convertor , similar to this one ..........

61wGJLcYv8L._SL1500_.jpg




Thoughts ????? on this device

I'm asking because after looking through and reading reviews on Amazon , there are some pissed off customers and a few that are happy .
 
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Using mine yesterday, I found some holes in the speed range, I wanted a 1000 but had to settle for 800. When I worked in construction, our language was not suitable for the front parlour. We had a saying "good'nuff for the girls I go with." I think that might apply here.

After I finish my much needed second cup of coffee, I'll go back to trying to find the mistake I made installing my VFD on my lathe.
 
PeterT said:
close enough flange dimensions, but there were some variations to the shaft length/diameter/key
Click to expand...
This is why I made my own adapter to go from the 145TC ( 56c is an option too ) to that metric shit on the RF45.
I also bought a larger shaft motor ( 145 TC ) and opted for the 3600 rpm version, Turned the shaft down and milled a new key way ( diameter is metric and keyway is metric ). Attached it to my 3d printed adapter ( PETG ) and bobs your uncle!
None of that silly metric motor garbage.
 

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@Proxule I assume you pulled the rotor/shaft assembly & turned the shaft down in the lathe? How much effort removing & dealing with bearings & such?

I assume 145TC is an IMP spec, so an IMP shaft which you turned down to Xmm diameter the RF45 needed? And the adapter plate was needed to marry the IMP bolt pattern to (assume) metric RF45 bolt pattern?

Was your RF45 motor kaput or you wanted to replace/upgrade for other reasons? I recall the stock spindle speed was ~1800 RPM but I can't recall if that was the 1:1 to motor spec or reduced. Are you saying 3600 RPM you doubled the speed?

I see a big capacitor box so its single phase, were there any issues integrating the wiring or that aspect just stays with the motor itself, not the machine stop/start?
 
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