[Shensai]

I have a Mazak 400-IIIST with an Mazatrol 640MT Pro System. My problem is the flood coolant pump won't come on. I have checked everything I could but found nothing wrong except that the contactor won't pull in when I call for the pump. My question is, what controls that contactor? Is there a relay or fuse I'm missing?

[Night Shift Wiz]

You need to check the schematics. Could be a relay or a solid state relay. Don't think you'll find a fuse.
You also need to check the interlocks. Coolant won't come on if the ATC or pallet changer doors are open or their prox switches are misreading them as open.

[Shensai]

The only thing I'm finding in the schematics are the motor and contactor. Nothing even remotely like a relay. Unless I'm reading them wrong. As for the interlocks, I thought of that but the other coolant functions work fine so I have ruled them out.

[Al_The_Man]

If the coolant is by M code then it will be fed off of a output, these can vary from line driver IC to small printed circuit relays on the output board, you should refer to the machine prints and trace it back from the contactor coil.
Al.

[Night Shift Wiz]

First thing to do is to go into diagnostics and verify that the Y output for your coolant pump is high. That in turn is probably sent to a board that turns on a solid state relay which sends power to your contactor coil. But first it will go through a contact on the contactor thermal heaters.

Did you get a thermal trip alarm first which you reset? Could be the contact in the heater is bad or the SSR is bad. Or a loose screw on a terminal strip in between the components. I'm assuming you're not getting voltage to the coil.

[SoCalPE.com]

Might be a dumb ??? but did you check if the coil on the contactor is even getting voltage?

[Shensai]

Yes. I did check to make sure I have power going to the contactors. No thermal alarm, or any other alarm. It's not an M code but rather a softkey command. And the prints I have don't show any relays, SSR or other.

[SoCalPE.com]

If you have your voltage to your coil on the contactor and it's still not pulling in then the contactor is bad.
In total you should have two voltages going in to your contactor, most likely 24v to the coil and 120v to supply to the motor.
If I read your post right this seems logical. Good luck.

[Al_The_Man]

If it is a soft key or or any type of controller command then it will be an output of some kind from the controller, It should not entail that much to trace back from the contactor coil to where the supply is missing.
Typically it would go back from the coil to a O/L interlock on the contactor itself and from there to either a outboard control relay or to an output on the control itself, where either the control relay or the coil itself is fed by a SSR output, line driver IC, or equivalent.
Either way it should show on the wiring schematics if you have them, otherwise use the reverse engineering method.
Al.

[Night Shift Wiz]

I have a Mazak 400-IIIST with an Mazatrol 640MT Pro System. My problem is the flood coolant pump won't come on. I have checked everything I could but found nothing wrong except that the contactor won't pull in when I call for the pump. My question is, what controls that contactor? Is there a relay or fuse I'm missing?

The page on your prints that you are looking at probably just show the motor and the contacts that feed the motor. There should be a number by the contacts, probably KM something, that designate the contactor name and the coil (there is probably also a page number where to find this coil). There should be another page in your prints that show a Y output that goes to a coil with the KM number and also called Flood Coolant. That will show you what controls the contactor.