rotary encoder erm 280

[brainlessme]

my five axis grinder is fitted with a rotary encoder from heidenhain (erm280). Controls are fanuc 160i.
I think we may ve gotten some oil into the encoder area. and were getting following alarms
1. Pulse Miss
2. Over Current etc,

We cleaned the encoder without dismantling it.

The axis tries to find a position as soon as we press the Jog button (when the machine is started). When we press the B Axis button to try to jog it... it is either locked and gives and OVC alarm. or it momentarily rotates at high speed and generated a Axis Excess Error.

any idea of what is causing this.
also how do i clean the area betweent the reader and the ring. The gap is too small. We may have some oil there. But is this the cause.!!!

[Al_The_Man]

The only hope you have really is to wash it out with de-natured alcohol and allow to dry.
You would have to confirm the output with a 'scope, I don't have the info on the erm280, it could be 5v TTL or 1v p/p sine wave.
Al.

[brainlessme]

hey Al thanks for the info....we finished cleaning the rotary drum and the encoder reader with the alcohol.

Unfortunately we had to remove the encoder to be able to clean it correctly. it contained moisture and bit of oil.

Also the surface has straight lines...very light tho as if it was lightly rubbing on the drum or something (which is impossible with the two strips on the side).
but now after mounting (using a .15mm gap filler as advised) the encoder does not display the change in reading when we manually rotate the B Axis by hand. Nor are we able to move the axis using MPG handwheel. All other four axis show change in readings and can be moved in MPG JOG and home conditions.

But the Baxis when trying to jog, oscillates in +/- direction and causes a 436 : Soft Thermal (OVC) alarm after which we have to restart the machine.

And yes we have checked the 5V supply and it is pretty good!!!