Mill motor challenge fun times - what type of motor is this ?

[nick mulder]

I have an Emco milling attachment for my Emco Maximat V10

When I got it the electronics were listed as dodgy and sure enough turning it on it caught fire

I've replaced the lathe motor with a spare AC servo I have here - not wanting to get into the original burned control unit nor fork out for a new motor for the mill I'm keen top learn about the motor there is on it - maybe I can use a spare drive (granite devices VSD-XE) I have here to run it ?

It has 4 wires coming from it - is this something easy to a. figure out what it is ? and if it is easy to figure out b. easy to drive/run ?

Pics here:

http://farm7.static.flickr.com/6211/...05480ca9_b.jpg
http://farm7.static.flickr.com/6095/...6e1f69a0_b.jpg
http://farm7.static.flickr.com/6101/...326833e9_b.jpg

http://www.talkfestool.com/vb/member...aximat-v10.jpg

[mactec54]

nick mulder

The motor that is standard on those machines is just a AC motor that runs at it's rated RPM, the gear box controls the spindle RPM

Both the Main spindle & the Milling attachment, you should be able to put a regular plug on & run them, Look at the tag on the motors they should be 230V

The main spindle AC motor, take it to a motor rebuilder, & have them check it, The starter caps could be all that is needed to be replaced

The may be 3phase, But most of these machines all had single phase motors, Just look at the motor Tag & it will tell you what you have

[mactec54]

nick mulder

Take the back off were your switches are if there is a cap in there like this drawing you have a Single Phase motor

[nick mulder]

Originally Posted by mactec54 nick mulder The motor that is standard on those machines is just a AC motor that runs at it's rated RPM, the gear box controls the spindle RPM Both the Main spindle & the Milling attachment, you should be able to put a regular plug on & run them, Look at the tag on the motors they should be 230V The main spindle AC motor, take it to a motor rebuilder, & have them check it, The starter caps could be all that is needed to be replaced The may be 3phase, But most of these machines all had single phase motors, Just look at the motor Tag & it will tell you what you have

Single phase input but the mill motor has 1 ground and 3 other wires.

Motor tag isn't on the motor but I can tell you all about the lovely pins that held it in place (no idea how many previous owners)

I'm happy with the motor I have on the main spindle now, its much more powerful than the stock version (yes, I'll be careful I don't ruin the drivetrain)

The main control is burned, there are caps in there - but no idea what ... I had to wheel the whole thing quick smart out of the garage into the driveway then deal with it, as simply removing power didn't stop the flames.

Motor rebuilder sounds like the go - or maybe an Emco maximat circuit diagram.

I know my other mill has start and run caps that switch with a centrifugal set up, I thought maybe thats how the four wires work - but nothing like that in here ...

[Al_The_Man]

Three wires plus gnd on a 1ph motor would be non reversable type.
Did the controller that went up in smoke feed the motor? if so it may have been a VFD of some kind, if so the motor would be 3 ph, and if there is no centrifugal actuator on the armature may confirm 3ph.
Al.

[hub]

4 wires to motor = 3 phase. Likely a VFD like Al said. The input to the the VFD is 1 phase.

The "electronics caught on fire"; that migth be:
- Driving a too large motor with a too small VFD (without overload detection)
- Damaged motor (again without overload detection)

Al, "Three wires plus gnd on a 1ph motor would be non reversable type."
I have never ever seen that so far, could you explain if you don't mind?

Hub
- Overheating (not good enough driver heat management)
- Other (many) possible faults....

[Al_The_Man]

Originally Posted by hub Al, "Three wires plus gnd on a 1ph motor would be non reversable type." I have never ever seen that so far, could you explain if you don't mind? ...

For reversal, usually both ends of both windings are brought out, 4 wires.
If the motor is made uni-directional, the 'common' end of each winding is connected internally and just the common conductor brought out, this leaves two ends, one for the start winding one for the run, 3 conductors in all.
Al.

[mactec54]

nick mulder

Here is a parts PDF that you can get from this site, the PDF was to big to down load here
just look up your model, it shows a little of the wiring for the mill head

EMCO Hobby Machine Instruction Manuals and Spare Part Lists

None of these machines had VFD for motor control, unless someone put a VFD on a 3 phase machine, which then could be run on a VFD

If they had 3 Phase on your machine as you will see in the parts manual, They have different switches, & a starter for the main power On switch,

The switches on your machine are for single phase

They have very simple wiring, on/off forward/reverse nothing more to it, so not sure what the fire was all about, somebody been playing & did not get it wired right

[nick mulder]

Putting on my fire investigator cap the burned control unit appears to be a large cap, and the rest is mostly plain old mechanical switching and nothing substantial electrically that I can figure out ... If it's of interest the lathe motor has 7 wires, but I'm ok with the servo I have on it now so no need to fix that - BUT I found another cap in the pile of bits that came with the lathe, its smaller and has that motor start/run kinda look to it:

5uF 250V

(the mill wasn't connected for the flame fun)

....and also - I don't know why I didn't find this earlier:

"OK, I've got my manual in front of me now, and it looks like I can clarify everything to the point of absolute opacity. One diagram is for the V10P. For the vertical head motor, single phase, 60 cycle, it shows: Black, Blue, and Brown. The capacitor is between the Black and the Brown. An adjoining drawing shows a Yellow-Green ground wire in the cable, also.... ...Each of the two motors has it's own separate capacitor, and there are no centrifigal switches...the caps stay in the circuit all the time."

MAXIMAT V10 milling attachment - The Home Shop Machinist & Machinist's Workshop Magazine's BBS

and also discussion about the cap value:

Permanent split capacitor motor question - Page 2 - The Home Shop Machinist & Machinist's Workshop Magazine's BBS

But it's discussing a 110VAC model and a 50uF cap, which they think is too high - I'm in the land of 230.9 V - shall I just wire up that 5uF cap between black and brown then um, phase to Blue then hmmmm, neutral and earth to green/yellow ?

Does this sound electrically safe ? I'll wear welders gloves, a facemask and jodhpurs when I probe its bits with a DMM

[Al_The_Man]

Do not connect neutral AND earth to the same point, you should have around 240 and neutral.
But the post you point to mentions yellow/green as a conductor which as per another post for a ROC machine here it seems they used this colour as a conductor, although this being a European machine I would be very surprised if they did this.
The voltage does not affect the cap value, only the working voltage, as the winding inductance remains the same.
What is the seven wires you mention? I though it only had four?
If it is 1ph and does not have a cent. sw. then it is Cap run type.
Was this a first time hook up when it caught fire?
Al.

[nick mulder]

Thanks for the link to the parts list...

Saves me from forking out 25quid for one !

the pic here shows the milling motor:

http://farm7.static.flickr.com/6219/...c174098a_b.jpg

'16' has two listings for the 'motor FFD' type: 8uF 300V and 20uF 330V
and then '16' again under 'motor garvens' type: 20uF 330V

These are brands ?

The control in that .pdf is a newer type than mine - pretty swish looking !

In 4 years of manual machining I've never needed reverse - not sure if that means I'm doing things properly or theres something I know nothing about

Shall I still give that 5uF cap a whirl ?

[Al_The_Man]

5µf might be a tad low, but all that will happen is it will be slow at starting, but if not connected to anything in the way of load, it should start.
If cap run then both winding may be identical, so as long as you identify the common, you may not have any problems.
Al.