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3 phase mishap, machine stuck in estop now?

Noobiecnc

Plastic
Joined
Jun 12, 2022
I have a 86 matsuura mc500v2 with a yasnac mx2 control and a phasamatic r15 phase converter. I also picked up another phase converter that i decided not to use cause it's a 10hp but the machine also seems to startup fine on it.
When I was replacing the 10hp with the 15hp I must of not used my man hands on one of the leg terminals because a wire slipped out after i verified voltages🤦‍♂️
before I caught the disconnection, I was trying to home the machine and the servo power would just shut off but you could just reach up and push the servo power back on and it would go again and go for a bit more and basically estop itself again.
After that is when I was investigating my power and discovered some weird voltages and the pulled wire shortly after. Got that all repaired and all connections double checked and now the machine control has alarm "emergency stop" and "servo power off"
where should I be looking for the estop condition that is keeping me from turning on the servo power?
I was trying to home the machine (x and z got homed) and know for a fact that there is a second step limit switch that will kill servo power. Would it be possible for my x axis to go past its home switch and be stuck on that switch? My overtravel release switch has no effect on this problem. Did I burn something up?
 
Is it a braked motor ? There should be a pair for 24 v to release the brake, running braked will cook a phase usually, takes 24 to open, 0v is closed
I found that out as a machine in work got a motor rewind, simple job to refit but I was on holiday and they got an electrician from the plant to fit it, he didn’t connect the brake lines into the e stop loop, burnt the motor out…again
I should have employed that Chinese girl who does motor rewinds on YouTube ,.. Genius girl fixes motor,
Mark
 
Is it a braked motor ? There should be a pair for 24 v to release the brake, running braked will cook a phase usually, takes 24 to open, 0v is closed
I found that out as a machine in work got a motor rewind, simple job to refit but I was on holiday and they got an electrician from the plant to fit it, he didn’t connect the brake lines into the e stop loop, burnt the motor out…again
I should have employed that Chinese girl who does motor rewinds on YouTube ,.. Genius girl fixes motor,
Mark
The converters don't have a brake. My servos have brakes but I'm not hearing the contactor that unlocks the servos when you give them power on startup. I'll have to pull some fuses and check.
The mill also seemed to work fine with the 10hp phase converter and immediately after installing the 15hp
 
My guess is one of the axis isn't happy, so won't let the system fire up. You just have to fine which one. Also, verify each of your axis positions isn't in a overtravel location.
 
You probably just have one or more tripped breakers in the cabinet, or possibly fuses given the age of the machine. Single phasing a three phase device causes it to pull a lot of current. CNC machines are generally pretty well protected about this kind of thing as you discovered when it was e-stopping itself.

You will probably have breakers feeding the servo amps, and they might be tripped, but some servo amps have internal breakers or fuses that you might need to check.
 
So I checked last night and got my x axis off the home switch and still nothing.. (y and z were in the middle of travel) I broke out the multimeter and started plugging away at my power converter that supplies all the other voltages to the machine and I have no power 5v/12v/24v
The easy fuses i can see ohm out fine. I'll take a closer look today when I get home.
Fingers crossed I didn't let the magic smoke out. All my servo drives seem to have their 200v+ but if my estop is 24v than I just have to trace down why I'm not getting my low voltage power to the machine.
 
This is the estop chain documentation for my mc500v.
 

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Power converter, do you mean transformer?
Bill D
Ok so the technical term i was looking for I found in my manual is "composite control power supply unit" that will now be dubbed "cps" for short. Which does transform 200+v down to 5v 12v and 24v

To clear up any general confusion from how I described the situation
-got mill home
-hooked up phase converter
- successfully verified operation
-Replaced phase converter with a nicer 15hp model
-Successfully verified operation (or so I thought anyway)
-few days later, I'm loading tools to run my first program
-y axis homes fine, servos powered itself off while I was doing x
-confusingly pushed servo power on again and things start working however homes were reset
- finishes homing x, homed z, servo powers off while homing y...
- i grab my multi meter and open up the power cabinet and start measuring input power which leads to more confusion because stuff isn't what its supposed to be
- shut down the rpc and machine and found one wire in the box where the single phase input/rpc/three phase output to machine had slipped free from its contact (specifically a 120v leg of the 3 phase going to the machine was disconnected. Not the wild leg)
- fixed connection problem
-fired everything back up and my control screen comes on. Estop error won't go away and I can't initialize the servos with the on button now so there hasn't been any cnc movement since.
Exactly how it happened, machine was on for probably 5 min
I didn't crash this machine, I only know about the emergency switches because of transport and the table/z moving on me. This machine has extra stop switches for redundancy to prevent a hard crashs of the castings
 

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Sticking contactor potentially?? I pushed this contactor on this other power board and heard the noise I've been looking for so I went back to the control panel and everything worked fine. I wonder if it was just not seated right or something. Is this a sign the contactor is going out or is this just some fluke caused by low voltage?
A contactor is just a HD relay right? Its not like a circuit breaker?
 

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Sticking contactor potentially?? I pushed this contactor on this other power board and heard the noise I've been looking for so I went back to the control panel and everything worked fine. I wonder if it was just not seated right or something. Is this a sign the contactor is going out or is this just some fluke caused by low voltage?
A contactor is just a HD relay right? Its not like a circuit breaker?

Depends. Can you turn on/off/enable/e-stop the machine normally now, or do you have to manually operate that contactor every time to make it start? A contactor sticking does not necessarily explain an e-stop condition in leu of a more specific alarm, but it depends on what the contactor actually does and how sophisticated the control is with fault conditions.

Contactors can have overload trips built into them, but I don't see one on that contactor.

Contactors can fail in a few different ways, but they don't fail often. "Sticking" contactors usually fail the other way round - they will fire, but not release. It seems more likely to me that whatever control circuitry enables this contactor is at fault, but again, does it work completely normally now?
 
Seems to be. Last night I started the machine twice and run through every possible combo i could think of on/off/estop buttons and everything seems to be totally back to normal. I did this all before bed though, ill load my tools and give it another test today after I get home
I do agree that it seems like an unlikely fix to my problem as the contactor clearly fires with some force with as much noise as they make engaging but that is the only thing I did on this peticular time I was out there.
 








 
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