Need Help!- MAZAK Slant Turn 15 / FANUC 6T PULSE GENERATOR INOP.

[nybuxt]

I have a MAZAK Slant Turn 15 with FANUC 6T controls that I recently purchased and just powered up.
The only function on the machine that DOES NOT work is the moving the x & z axis using the hand wheel/ pulse generator. I checked for power to the pulse generator - 5V which I have, and also 24v to the x/z axis selector switch, which I have.
Is there a way to check the pulse generator to see if it is functioning using a multimeter? Other than the physical wiring and connections are there any other items which I should look at? The wiring manual which came with the machine is basically useless so any input would greatly be appreciated before I start sending out the boards.

[Al_The_Man]

The pulse generator outputs 100 pulses/turn, you should be able to put a meter between common and one of the outputs and see the change when you turn the wheel slowly.
Check each output.
Al.

[nybuxt]

Al,

I checked the output of the pulse generator with a digital meter... when I slowly turn the wheel one click at a time the meter jumps, as I increase the speed I start to read voltage up to about 2.5 v. It seems to me the pulse generator is working and the problem lies elsewhere......but WHERE?

Any thoughts?

Thanks, NYLE

[TWPguy]

Has this problem ever been resolved? I'm having a problem with a mazak v15n. I can move x axis with the handwheel but get nothing when I switch to y or z axis.

[nybuxt]

No, the problem has never been resolved completely. For a while now it seemed to be working, but in the last week I have found that it only works until you "Home" the machine. Once you "home" the machine it stops working. I'm guessing it's a board issue, but the wiring manual I have for the machine is so useless that I have no idea which board to check. Thought's anyone???

[fordav11]

The MPG operates only with 5V. When turning the handle the output should pulse from 5V to 0V. If you are getting only 2.5V that might suggest a bad connection. You may be getting 5V but your meter might not sample fast enough to register the full voltage before it starts to drop to 0V as you turn it so a meter may not help unless you have one that can sample fast (for example a Fluke 12)

If you have access to an oscilloscope you can check the output signal waveform to make sure its correct. It should output a square wave with peaks at 0V and 5V. Also check both phase A and phase B outputs. The MPG should have 4 wires. 0V (i.e. ground), 5V, A Phase Signal, B Phase Signal. Both phases should output a square waveform at 5V with 1/4-phase difference between the 2 phases. To check that you would need to connect both phases to the scope. You'll need a dual trace dual timebase scope for that.

Does the screen show HND when you switch the mode selector to handle?

If no check your mode select switch.

If yes, the next step might be to trace the wires to the connector on the circuit board. I've done a lot of repairs where a signal was partly there but there was resistance around 1000 ohms caused by a build-up of crap. Find the connector and clean it.