Problem- Boss 9 Axis Drive Fault won't go away

[Aplus]

I am new to posting on this site. I have a Boss 9 controller and can't clear the drive axis fault. Sometimes the relay pulls in for the drives when I push the enable drives button and I get the "Squeal" when the drives enable. There is holding torque on the X axis motor and am assuming the z and y. The little red light on the enable drives button on the front never turns off. Any suggestions where to start.
I have worked on many other Yasnac and GE equipped machines but this is the first Boss 9.

[machintek]

Check the BOSS and FIST event monitors for fault logs.
See if all 3 (one on each axis drive) red LED goes out. This means that drive is enabled and has no faults.
How long have you had this machine? Have you checked power to it and does it agree with the trouble shooting section in the maintenance manual?

George

[Aplus]

I recently purchased this machine however I have been around it for around 5 years. Previous owner replaced the drive belt in the head and from that point couldn't clear the fault. Can't think there is a relationship there however I have seen stranger things before.

[Aplus]

I was able to check the monitors once via pressing Help, 3 or 4 enter however it seems to lock up now once I press enter.

[Aplus]

Red lights on each axis drive blip on for around 1 sec when powering up. No other lights that I see on the drives.

[machintek]

Wierd. Red LED on drive means drive off or fault. Should be on until you turn on drives.
If drive belt in head is changed, I usually change the movable vari-discs and associated bearings. Should not have to touch much else. The control CRT and front panel are hinged and move away. There are switches on the quill for over travel but these would display a axis limit fault.
I would go through each part of the trouble shooting section and make sure all voltages are there.

George

[Aplus]

OK I started checking voltages per chapter 7 Troubleshooting. Everything looked good until note 5. Measure the output voltage to transformer T2 between terminals marked #211-2, #212-2. The original reading was about 56 VAC. Book states 90 VAC. Started checking for loose connections-Found all to be tight. This paragraph in the manual has in BOLD "MACHINE" and under it has A11. I don't understand that. I checked the taps on the input side and they were not hooked up according to the chart on the transformer. Can't say what they were before because I had a helper and the wires were changed before I could record where they were. So anyways, now they are hooked according to the chart on T2 and now the voltage across 211-212 is 190 VAC. The book calls for 90 VAC. I have a spare T2 that came with the machine so I temporarily wired 230 VAC into it and it reads 190 VAC also. The voltages for wires 1-2 is right on 120 VAC. Now I am afraid to push the fuses in for the output of the T2, Any suggestions. Thanks.

[machintek]

Look at the schematics. One sheet should have all the transformer connections listed in a table. My laptop crashed (keyboard failing to respond-mother board went bad) and I have no data with me.

George

[Aplus]

My prints have the same connection callout that is printed on the transformer and that is how it's hooked up now, T2 PN 1541540. The note calls fo 90 VAC and I am still getting 190 VAC between terminals 211-212. I don't think the 90 VAC a misprint, I have several manuals that have the same info in. Not sure what to do next.

[machintek]

What T2 do you have? My prints show 2 types. At 230 VAC, one has jumpers and one does not.

George

[Aplus]

Mine has the jumpers. I posted the PN in one of the previous post.

[machintek]

Look at page 4 of the schematics showing the drive power supply.
There are 2 ways to go from AC to DC. The top of the page shows full wave bridge rectifiers.
The bottom shows the T2 in question with the other way of getting DC. It uses a center tap transformer going into individual diodes to get DC. So yes, you should be measuring each side with respect to ground. Better yet measure the DC between wires 249 and 250.
But if this is within spec, you are back to square 1 in trying to figure out what is going on.

George