[McCoyHeavy]

Help please...or at least a troubleshooting clue

on a macturn 250w, upper spindle (M) I am getting 1170-22 MCS Magnetic Encoder alarm, MA axis 4B0095F

This happens whenever Speed starts to get much above 700 RPM. I can gradually increase the RPM to about 1100 once it is running before getting this error again. Error occurs instantly when it crosses the magic number, the "SB" value drops...

IF, however, I run the spindle in the opposite direction, and set spindle to SB=200 for example, the spindle seems to hit 200, but the display SB value on the screen fluctuates around 7 to 8, then occasionally hits 200 before dropping back to 7 or 8. Ultimately I get this same error or an error saying speed could not be determined.

If I do a M603 or M602, no prob. Machine flips tool 180 degrees and locks. If I do a manual jog, no problem either.

Assuming (and this may be a big assumption) that the encoder is the 6 hall effect sensors under the head cover, I took off the head cover and see they are all lit orange. They do not change color when the spindle moves. Pulling one out turns if off, putting it back in changes back to orange.

So, is there a diagnostic screen to help (This is OSP E100L, btw)? Or any helpful suggestions? I really want to fix this myself as the local Okuma repair guys are expensive and seem to spend more time pondering and calling back to HQ as if this is the first Okuma they have ever seen

[Algirdas]

I took off the head cover and see they are all lit orange

You need multi channel osciloscope for 'sin' 'cos' adjustment now. When this fixed, you can step forward back to original problem.
By the way. Check the junction box, if it's dry inside. The junction box where cable of the encoder goes to

[McCoyHeavy]

OK..1) Yep, rusty ground, water is inside junction box, but "outer" junction box is dry....not sure how inner box is wet and out box is dry. Must be the exit/entrance hole behind connector panel.
2) When I tested the sender, I did not move it holder at all [knew enough not to touch those screws]. But moving the sender in/out i.e. only towards spindle center...would that really screw up the world? If it WOULD where would I find adjustment technique/instructions?

THANKS, I am now drying out box .

(Terminal block just crumbled as I touched it...very corroded on the "B" terminals, which is where i was getting error. So hopefully a quick trip to home depot for a low voltage terminal block will solve this.)

[Algirdas]

coolant didn't reached the next box because it travels via wires (capillarie)

moving the sender in/out i.e. only towards spindle center...would that really screw up

doesn't hurts to check. Initial problem is coolant penetration. sin cos adjustment/check normally is done with (at least dual) multi channel oscilloscope at range of speed. If you check the sensor signal with oscilloscope you will see how far from theory it is and how steep it reflects the air gap.

[McCoyHeavy]

Wiring dry, all connectors de-corroded....problem still exists. Weird bit is that is WILL run at like 400 or so RPM...and if you advance speed slowly, it works up to about 1000 or so. Wiggling wires, does not cause any prob. So I guess air gap check with silly-scope unless there is a better idea or some built-in screen that shows what is happening.

[Algirdas]

Wiring dry

nice connectors is a good sign. You can't notice "wet" wire, which works as capillary. check the situation on other end of wires where coolant can reach. Most likely, all these lines go nearly to the same place

air gap check with silly-scope

with single channel You can adjust to get nice form on the speed range. No way to see sin cos shift. The same if oscilloscope is cheap "double ray", without real dual-channel input. You need a screen of at least two signals synchronized and in real time