What's new
What's new

Miller CP-200 208/230v converted to 240v single phase

CRJarvis

Plastic
Joined
Apr 23, 2017
miller CP200 208 230v 022 263.jpg
https://scontent-ort2-2.xx.fbcdn.ne...=f0f062cd572ea6681053b1062ce8a834&oe=5B57FB6D

looked up the manual:Miller CP-200 208/230v serial # HH025651
Serial Numbers: HG044019 through HK229133 (ours is serial # HH025651)
Owners Manual: English PDF 404 - File or directory not found.

any help on this one? As i was wanting to do the "Haas-Kamp" Single Phase Conversion on it and now am not sure seeing it is a 208/230v.

I have seen as i have searched the forums for anything on this and
Dave Kamp Said "By virtue of a forum member who's acquired a surplus CP-200 in hopes of a conversion, It has recently come to my attention that there's ANOTHER flavor of the CP-200 out there... Craig found a CP-200, and noted upon opening it, that the jumper configurations were different from those shown in my step-by-step. He contacted Miller's support staff, and acquired a copy of the manual, and to our surprise, the unit is listed as a 208-230 ONLY unit.

The topology is essentially same as the 230-460 unit, with exception that the transformer primary coils are not two-section series/parallel, but rather one single 230v winding, which has an extra tap for 208v."

and am wanting to know has anyone converted this one yet?
and is this the one i have? will post more photos of it.

have a 30 HP Roto Phase i built set up for 208/230V can it run it or would the 3rd leg voltage differences mess with the welding? or burn it up?
 
20180429_151429.jpg
this looks like its the 208/230V only.

View attachment 227139

have a 30 HP Roto Phase i built set up for 208/230V can it run it or would the 3rd leg voltage differences mess with the welding? or burn it up?
 
Last edited:
The alternate concept is based on a major IF... IF the transformer primary is delta, or IF the machine is WYE.

If the transformer primary input is delta, the coils will be close enough (230v) for 240v single phase, they can simply be disconnected from the delta-interconnect jumpers (A-B/B-C/A-C), and then, the A and C coils can be connected direct to Red and Black... with the C coil is wired out-of-phase from the A coil... and the B coil connected through to Red and Black with a capacitor in each lead... no Delta-Wye alteration of the output contactor should be necessary.

IF the transformer primary is WYE... that means each coil is 120v or so... the method would be to wire A and C in series, with the phasing of C reversed, and then connect C across the red and black with capacitors in each lead... HOWEVER, the capacity would need to be recalculated in such a way to LIMIT current flow through the coil. Unfortunately, the inductive character of the transformer coil is dependant upon several variables, and an error in value has the potential of yielding catastrophic results.

Realize that when Peter and I wrung out this conversion concept, we utilized some basic electronics math in order to determine a BALLPARK of the capacitors' values, knowing full well that the inductive properties of the transformer were not only variable, they were unpredictable... but we COULD depend on the coil's AC impedance to be AT LEAST enough to limit current at the CP-200's applied coil voltage of 480-Y (277v), and in my testing, I was only applying 240v, so there'd be no issue of catastrophic overload. Once operational, it was clear that the concept would work, and that while the inductive character of the transformer DID have an impact on how the conversion performed, empirical testing and adjustment of capacitor values yielded an excellent result.

This second alternate, throws another sail in the wind- using the capacitor's phase shift to not only DRIVE the center coil, but also, provide enough impedance to LIMIT current through the coil... because we'd be driving a 120v coil from 240v mains.

The last possibility, is that we could utilize the phase shifting capacitors, and drive it between one hot, and neutral, but that would put HALF of the welder's load on the neutral lead, which is not really good practice for a machine or shop tool.

So... I can't give you any guarantee of what values would be used, or any level of confidence of wether it would work... but I can guarantee that, if done wrong, it'd have some pretty bad results... that's why my answer is open-ended. When I get one in my shop, I'll actually be able to try it.


NO- Absolutely not!

With it getting 208v across each leg A-B, B-C, C-A, in WYE, that means the voltage across each COIL is subjected to about 125v.

If you break the wye, and apply 208 across each coil individually, you'll be subjecting it to a substantial overvoltage, and it WILL expire.

As I noted before, it is very possible that an alternative method COULD be used, but I haven't had opportunity to work out the details.



Damon- If you look back at my previous post (#28, titled "NO!"), you'll see that I explained why.

You need to have 240v across the two in series. Each coil is 120, so 120+120=240. The PROBLEM, is that CENTER coil... it can't run on 240... it will melt.

In this conversion, the A and C coils are NEVER fitted with capacitors.

Now...

If you really, really want to try this (and it sounds like you do)... then I'll give you the following suggestion, with the following caveat:

Totally At Your Own Risk. Totally. I'm not there to see, help, or provide ANY insight, nor protect you from any sort of danger. I will accept NO responsibility for the result, because I've never had a chance to attempt it... nor do I particularly like it...

The center (B) coil: Connect a wire to one of your LINE connection points. Run that to a capacitor.
Connect another wire from your NEUTRAL connection point. This would be the WHITE wire coming from your line cord... run that to ANOTHER capacitor.

Run leads from each capacitor to each lead of the B coil. Doesn't matter which.

At that point, you'll have A and C coils, in series, driven by 240v... and the CENTER coil (B) driven by 120v from one of the incoming lines, to NEUTRAL. IN this case, you'll NEED a neutral conductor through your line cord to your service panel. This technique is not what I'd consider safe or prudent, but it SHOULD work.

As far as your machine doing nothing... there's two issues... first, is that you're driving it on 120v... second, you may not have utilized the front switch properly. Look closely at the wiring of your unit... your line cord inputs go to three terminals on the terminal strip... from there, it goes through wiring to the front-panel switch. I'm betting that you selected one of the line switch wires that goes nowhere.

Hey Damon-

Some time ago, I was fielding inquiries about making the 208/230 units operate... What wiring combination wound up being the successful setup?

Dave,

The configuration that I went with was one that you had suggested some time ago. The top and bottom coils are wired in series reversed from each other and the middle coil is driven from one side of the 220 volts that goes to the top coil and neutral with run capacitors between the line and coil. I was very intimidated to do it this way in the beginning because part of the load for the welder would be put on neutral. after some contemplation and trying to simply wire all coils in series with capacitors, without capacitors different ways etc, with terrible results i gave in. I decided that it wasn't doing any more good sitting there in pieces than if it was sitting there in pieces with melted coils if something went wrong. I started by just wiring the top and bottom coils in series and leaving out the middle coil. I turned the power on and listened to the welder humm. It was a fairly steady humm. so I reversed the series connection to see if it would sound any different and it did. it sounded like it was fighting itself so back to the first way i went. Then I added the middle coil in without capacitors. sounded terrible. I then added a capacitor (63 micro farad i believe they are) and it sounded better. I decided to add another and it sounded better yet. I left the fan disconnected for the sound tests since it's so damn loud of a fan. I feel as though i need to add more capacitors or change one that is in there for a lesser value because the voltage and current fluctuates a bit when welding. I also had converted the secondary side of the transformer as shown in the original conversion process and I think I need to put that back because the damn thing is smokin hot. I also connected the wires for the 110 volt outlet on the front of the machine that powers the wire feeder to one side of the 220 volts I have coming into the machine.

Well, then that settles it... it was a wild-a$$ guess, and I guess it worked. When you say 'hot'... you mean, the otuput voltage is high? If so, yeah, run it in the original (delta) arrangement.... in 208 Wye, those coils would be normally subject to 125V... you're pushing 120 through 'em, so darned near perfect, just 60 degrees later... so your output ratio should be dead-on.

The output voltage sag under welding IS to be expected... that's called 'slope', and it's necessary to make the arc naturally stabilize as wire is fed out the nozzle. When you convert it back to delta output, it will reduce the sloping effect along with reducing the output voltage, so you'll see less indicated sag.

Can you draw out your connection diagram, and indicate the serial number, so that others can copy your work?


So I promised I would do the write up for the 208/230 volt units on Friday. Well it's 2am on Saturday so it's close enough :-) I didn't have time to get it done before I went to work. I have attached some pictures for reference. This conversion requires about half the steps that the other conversion requires so a little less leg work is required but we still have to thank Dave Kamp because without his guidance I would have never figured this out.

First and foremost: This is a write up of what I performed on my machine that was successful. I am not responsible for anything negative that may happen to you, your property, your dog, the neighbors dog, neighbors cat, neighbors bird,....well you get the idea.

What I did from the start:

1: gain access - you will want to take both side panels off the unit.

2: break apart the coils. I un-bolted the red board where all of the wire connect, took all the wires off and sat them aside. (I did this long ago and ended up losing them but I meant to re-use them. Keep them till you are done because I wish I wouldn't have lost them.) Each coil will have 3 connections to it. one of each will go to one of the others with a crimped on connector. I cut them off to break the 3 coils apart. There is one terminal that goes on the back side of the red board that has 2 wires going into it. leave this together just don't connect anything to it. you are going to use the one side of the coil that connect to another coil and the other ring terminal that has only one wire crimped into it. this is 1 and 3 on the wiring diagram.

3: run line voltage wires to the "off" side of the power switch as shown in the wiring diagram. (hint: do not have them energized) I put the neutral in the middle of the 110 volt lines but placement doesn't really matter so long as you match what you want on both sides of the switch. (hopefully that makes sense)

4: Connect one of the 110 lines on the "on" side of the switch to one of the terminals on either the bottom OR the top coil.

5: Connect the other 110 line on the "on" side of the switch to the other coil (bottom or top) but the opposite side of what you did on the other coil (ex: so if on instruction #4, you connected the 110volt line to ring terminal on the top coil then on this step connect the 110volt line to the side of the coil that you disconnected from the others.) Now connect a wire between the 2 coils so they are wired in series.

6: at this point in time I was curious so I made sure nothing was at risk of short circuiting and i plugged it in and turned it on. (from afar of course) and BANG!!!......Just kidding. The welder made a fairly nice kinda steady humm. so i turned it all off and unplugged it and inverted my connections on one of the coils and tried again. This time the coils sounded like they were fighting each other so i turned it off and put it back the way I had it. So basically what i"m saying is, it might be a good idea to make sure you are off to a good start before you go any further, if you are following this to do to your own machine.

7: now came time to add the middle coil. The middle coil will utilize the neutral line that has not been used yet. On my machine, the middle coil shares the 110 volt line with the top coil. There was no reasoning behind this besides thats just which one I chose to share it with. It likely could be shared with either one. The other side of this coil connects to neutral. BUT! in addition to this you are going to have to put capacitors in between the coil and the 110 volt line to perform the phase shift similar to how it is done on the original conversion. On my unit I have the capacitors only on the 110 volt line for the middle coil and NOT the neutral line. I had bought 2 capacitors for the conversion before I dove into it and realized that what I had was different than was was in the conversion. But it worked out because I ended up needing them both. I tried with just one at first and it had a decent humm to it, not great but it didn't sound like it was fighting itself. I added the other in series to the first and it sounded pretty damn good. If I had another laying around I would add it to see if it sounded even better but where it is right now is very very pleasing to me. (side note: You may want to try inverting your connections to this coil to get the electricity flowing in the correct figure 8 pattern. just listen for the different humms. they will be distinct and you will know. ) I believe I have 63 micro fared run capacitors. (2 of them in series). I do not know if a single 126 micro fared capacitor would produce the same results or not. I don't know why it wouldn't but someone smarter than me (Dave Kamp) might be able to answer that. I also was too lazy (excited to get it up and going) to put the resistors on the capacitors to bleed them down. I don't know if that would make a difference in performance either, but I will tell you this. Those capacitors will hold a charge for a L O N G time. (wink wink wink wink) (DON"T TOUCH THEM if you are lazy,...err excited like me) (end wink)

8: Side notes. The fan can obviously just be connected one side of the fan to one of the 110 volt lines and the other side of the fan to the other.

The 110 volt plug on the front of the unit, I connected to one of the 110 volt wires on the "on" side of the switch and the neutral on the "on" side of the switch because I wasn't sure if the transformer that controls this would put out the correct voltage and knew that I could get the correct voltage this way.

9: The secondary side of the coils that is converted to WYE in the original conversion does not need to be performed. I had done this in the early stages of my conversion and experienced erratic performance from the welder. There was almost no low head control and it was almost impossible to weld thin metals with it. I converted it back to delta under the instruction and explanation of it not needing to be converted from Dave. ( see earlier posts if you are curious)

Ok so thats about it besides putting panels back on and insulating everything. The left side panel (looking at the unit from the front) I only removed so i could get easier access to the 110 volt plug wires on the front of the unit. I also cleaned the brushed and lubricated the screw and chains that move the sliding doohickeys on the coils.

first picture is the wiring diagram I cobbled together.
http://www.practicalmachinist.com/v...ccessful-cp-200-conversions-208_230-cp200.jpg
128173d1422090044-successful-cp-200-conversions-208_230-cp200.jpg
128173d1422090044-successful-cp-200-conversions-208_230-cp200.jpg


second is showing the top coil (side that was disconnected from others)
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202334205.jpg
128169d1422088622-successful-cp-200-conversions-img_20141224_202334205.jpg
128169d1422088622-successful-cp-200-conversions-img_20141224_202334205.jpg


third is showing the connection between the top and bottom coil.
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202405340.jpg
128170d1422088648-successful-cp-200-conversions-img_20141224_202405340.jpg


the fourth is showing one of the connections for the middle coil.
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202422483.jpg
128171d1422088671-successful-cp-200-conversions-img_20141224_202422483.jpg


The fifth is showing and overview of the whole unit.
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202435857.jpg
128172d1422088699-successful-cp-200-conversions-img_20141224_202435857.jpg


I will make a post with a few more pictures right after this post since I can only post 5 pictures at a time.

MORE PICTURES as promised!!

first picture here is showing the connection for the bottom coil
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202533651.jpg
128176d1422090761-successful-cp-200-conversions-img_20141224_202533651.jpg


second is showing connections from the "on" side of the switch switch.
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202513969.jpg
128175d1422090736-successful-cp-200-conversions-img_20141224_202513969.jpg


last is connections on the "off" side of the switch.
http://www.practicalmachinist.com/v...cp-200-conversions-img_20141224_202550432.jpg
128178d1422090792-successful-cp-200-conversions-img_20141224_202550432.jpg


I hope that everyone that has one of these units is able to get it up and running like i did mine. I have done a lot of great work with mine thus far, even tho I'm an amateur welder at best, I have some good teachers that are guiding me and i'm getting better along the way. I will be happy to try to help clear anything up that I didn't explain well. I tend to get a little loopy this early in the morning after a long work week.

Bob#1, sorry for the confusion. Once you have the 3 coils isolated from each other you will have 3 connections for each coil. One of these connections should just be a bare wire at this point because it will be one of the connections you broke apart to isolate the coils. The other 2 will have ring terminals. You are going to want to power the ring terminal that has only 1 wire going into it. The ring terminal that has 2 wires going into it should be left alone and not connected to anything. Hope this helps and my apologies for the late reply.

Chris

Thanks for your help! damongooseman
with your description i managed to convert my cp-200 (Canadian Version) with no fires, in a couple of hours!


Quote Originally Posted by DaveKamp View Post
Congratulations, Johnny! Enjoy the CP... it's a sweetheart, and a beastie!

How's your 'Canadian Version' differ from the ones everyone else (myself included) posted on?
It looks to be(from the pictures) the same as Damons' 208 or 230 volt, so the the capacitor(s) get wired to the center coil instead of the top and bottom. Used it today, a buddy happened by the shop,(a welder by trade) while i was using it, and was impressed. So I'm happy!
 
CJ, Based on the volume of what you've quoted and re-quoted in from other threads here, I really can't tell where YOUR comments or questions are...
 
Sorry for the mess was tring to put all the info on this cp-200 208/230 in one place after I had dug it up from searching the other posts. You have any advice on what to do on this, what else to try.
 
Seeing that it's a 208 volt could I not possibly create an external box to plug the welder into with a capacitors in the Box let's say hooking L1 to one of the 220 lines L2 to the other 220 line or L3 depending on which one needs to be done that way and the capacitor to the remaining line and then make sure none of the fans or other electrical devices that use the 110 are hooked to the capacitor generated line could that possibly work (sorry posting from cell on lunch break)

ok i know this would be running @ 110V what should be at 230V so this would not be a good work around.

seeing it would be at about 50%
 
Last edited:
This is how it should look before you start cutting and moving wires.
CP200 208230 work1.jpg
any help on what to do from here thanks in advance.
 
what wire to unhook.jpg
so looking at what was said and looking at mine,
i'm not sure if i just unhook #2 coil wire and leave the others #1 and #3 hooked together?
 
the only wires you have to move.
1. take apart the the Coils (CCW)
hook CCW#1 with BC#3 that was on the back of the RB#7. Leave the Fan wire attached to RB#7 it has 110V going to it. (in this setup)
2. take CCW#3 and hook it on the back of RB#7 (yes in the place of BC#3)
3. take wire 2R/B #5 off the Back of (RedBoard) RB#5 move to the Front side on RB#4 this will be your Nuetral line from 2R/B (and let you flip direction of Coil #2 if you need to.) with out unhooking the Red Board again.
4. now to attach CCW#2 to the back of RB#5
5. you will need to Move the Fan wire off the back of RB#4 and put it on the back of RB#1 it has 110v from 3R/A
6. now you need to make a jumper wire from the front side of RB#2 to the capacitor
and from the capacitor back to the front of RB#5 (this will be your CAP power to #2 coil.) to change direction of coil, move wire on front of #4 to #5 and wire #5 to #4.
7. Make sure to take off the Jumper that links #4 to #5 (i just hooked it to #6 and let it hang down.

Miller CP200 208 230V setup info.jpg
 
208_230 cp200miller work.jpg
this Photo is missing the info i need below hope someone can help me out with it.

there is a few things i not sure about the size of the ‘MOTOR RUN’ type capacitors of 60 microfarad (uF),
with voltage rating of at least 370vac. ( i have 2 that are ‘MOTOR RUN’ type capacitors of 60 microfarad (uF), with voltage rating of 440v)
just not sure if i need 2 or if this is the right size.



and if i need to do this part on this setup or not?
Do i need to do i need to.jpg

CONVERT SECONDARY FROM DELTA
TO WYE
1) Disconnect and tape three large wires from upper
terminals of power contactor.
2) Apply jumper bar across three upper terminals of power
contactor
NOTE: Jumper bar can easily be made by
flattening a piece of 3/4" copper pipe, bending
and drilling to fit. Some contactor terminals are
in same plane, this one happens to have center
pole higher than the others, so I had to do
some bending to make it fit.

after re-reading it i did find that damongooseman said in post #48 http://www.practicalmachinist.com/v...cessful-cp-200-conversions-244600/index3.html
"I also had converted the secondary side of the transformer as shown in the original conversion process and I think I need to put that back because the damn thing is smokin hot." not sure what worked best for him have not got a hold of him yet.
 
manual for HGO44019.jpg

looked up the manual:Miller CP-200 208/230v serial # HH025651
Serial Numbers: HG044019 through HK229133 (ours is serial # HH025651)
Owners Manual: English

227137d1525031859-miller-cp-200-208-230v-converted-240v-single-phase-miller-cp200-208-230v-022-2.jpg20180511_031614.jpg
this is from the inside of my case. it the same one i found in the manual.
Circuit Diagram No. ca- 901 851
and mine is 901 850
 
ok so Miller sent me the left out pages that are no longer in the Manual.
this is how mine is before i moved any wires.
CP-200 208v239v wire diagram.jpg

CP-200 208v239v.jpg

i now have put all the wires back like Originally wired. wired in the Cap to Coil #2 the middle one taking power from the 3rd to power the Cap.
moved all the jumpers to be 208V. well then took off jumper on the 2nd coil running power from the cap to RB#6 and getting power for the Cap from RB#8
 
ok so i converted it back and hooked it up to my Roto Phase and still i get to weld for about 3 sec and then it stops the arc. but the wire keeps feeding any ideas on what this problem is?
found a video on a diffent model that had a problem like mine so i looked up the manual and found this.

DIP Switch S1 On Motor
Board PC1
 Setting Current Detect
Override (S1-1)
Current detect override is used to
disable automatic run-in when a
welding power source is used that
doesn’t provide current feedback
through the 14-pin receptacle.
Install wrapper when finished.

have cleaned the Coil contactor 115 Volts mine kind of looks like a Cutler Hammer but not like the drawings.

now to get it set and test it again.
 
Last edited:
so after setting it up and getting it running like it should on the Roto Phase,
i will might go back and give it a try again ( seeing i know how it should work and sound )
but for anyone else that wants to try this i would not follow what damongooseman has done.
( at least until he gives better instructions of what he has done. )

The easiest thing i tried and it was what worked the best of all i had tried.
was to just use a CAP to power the middle coil L2 running 110 to L1 and the other to L3.
now the coil 2 and coil 3 did get warm so do not think this worked like it should. if i do more testing i will let everyone know how it works.

what i think i needed to do was to reverse direction of coil 3. but not sure how to do that with the way it is wired. this would put it 180 out of phase of coil 1 and 90 out of phase of coil 2. ( with running it on 208V settings.)
 








 
Back
Top