1981 Mazak Powercenter H20 help/advice wanted...thanks

We have a 1981 Mazak H20 we have been using since 2004. We've been able to fix issues in the past but are stuck with a problem.

We have basically NO knowledge on how to diagnose the current problem.

The problem revolves around the tool loading and unloading operation. The tool changing arm goes to grab the tool out of the spindle drive but the unclamp solenoid doesn't unclamp, so the eye doesn't "see" it unclamp and the machine malfunction light goes one and it stops.

Everything checks out back to the printed circuit solid state relay board. We are quite certain the board/relay on the board is NOT getting a signal from the computer.

So we think either the computer has an issue or something is telling the computer to NOT send a signal to the relay board.

If anyone has any insight to help or knows somebody near Fargo North Dakota that could help us it would be much appreciated. Also, time is becoming an issue since we are basically out of business until we get this machine up and running again.

We called Mazak but when they realized the age of the machine they figured they could not help.

THANKS
Chris

Weivoda Auto said:

The tool changing arm goes to grab the tool out of the spindle drive but the unclamp solenoid doesn't unclamp, so the eye doesn't "see" it unclamp and the machine malfunction light goes one and it stops.

Click to expand...

Usually in any sequence there will be sensors. Before the next step can occur, an "arm in position" (for example) sensor needs to tell the control that it can proceed to the next step. Often those sensors go kerblooey. If you can access the pic, you can see where the sequence is getting stuck.

You really need the manuals to troubleshoot these problems

Hi, thank you for responding. All the sensors are working with a tester and the wires are good as far as I can test before they go into the "computer". Sadly, I don't know how to verify that the computer is seeing them. We have the manuals but don't really understand how to use them to help us.

Update, we found a guy who could trace the circuit (about 15 hours worth) and test the boards. A small relay on one board was bad and a microchip on an I/O board was shorting to ground.

All fixed and we are up and running again.