JEOL stage not getting to where it should be...

[jtmitchell]

Hi all,

I recently have my 8530F Plus serviced and I've noticed that the stage doesn't seem to be getting to where it needs to be when I'm running things through PFE. It starts off fine, but I noticed that the last map I ran yesterday was slowly slipping downwards and the points I had queued up were off by a few mm this morning even though I'd double checked everything on Friday before I went home. I remotely accessed the probe this morning to check on things and spent a while putting everything back where it should be...

This wasn't an issue before the service (or after my last service) BUT I also had a harddrive failure and replacement at the same time (it was the D drive on the PFE PC, so nothing too bad but just where PFE reads everything to) so I'm not sure if it's definitely a JEOL issue or if there's a calibration that I need to do on the PFE side of things. The stage values on both the JEOL and PFE side match.

Any help would be appreciated as my lab is heaving for the next few months 

[Probeman]

Sounds to me like your service person may have messed up something on your stage, but you can try restarting the electronic probe electronics, and see if that helps.

I assume you're sure that the sample isn't loose in the holder?

[jtmitchell]

Sounds to me like your service person may have messed up something on your stage, but you can try restarting the electronic probe electronics, and see if that helps.

I assume you're sure that the sample isn't loose in the holder?

Yep, the samples are really well attached so I'll try restarting the electronics first thing on Monday and see if that does anything. I'll give JEOL a shout too and see if I can get them back in quickly to give it a check!

[John Donovan]

Sounds to me like your service person may have messed up something on your stage, but you can try restarting the electronic probe electronics, and see if that helps.

I assume you're sure that the sample isn't loose in the holder?

Yep, the samples are really well attached so I'll try restarting the electronics first thing on Monday and see if that does anything. I'll give JEOL a shout too and see if I can get them back in quickly to give it a check!

See this topic:

https://smf.probesoftware.com/index.php?topic=1394.0

Particularly this comment:

It was not a PFE issue, it was 8200 stage controller issue. John had repeated this to us several times but our service was refusing to hear it.

The 8200 stage controller board has failed and is sending a motion complete flag immediately after the stage move command. PFE senses this motion complete flag (as it should) and stops the stage (as it should). The reason the problem does not appear in the JEOL software is because the JEOL software completely *ignores* this motion complete flag and instead simply waits for a fixed period of time.

The change John made to the PFE code for us is to ignore the motion complete flag for a fixed amount of time, just as the JEOL software does. The new parameter is in the Probewin.ini file and is called "JEOLMoveStageMilliSecDelayAfter".

Now we can work without being scared of losing part of our results because the system is measuring in the wrong positions. For our team it is the best event of this autumn - thank you, John.

[jtmitchell]

I've got everything working again! There were no issues with the lead screws (they were replaced and the issue persisted), but instead the scintillator cage was catching on the stage as it was moving underneath and causing the issues. I had the cage replaced, the stage recalibrated and it's working perfectly once again.

[John Donovan]

I've got everything working again! There were no issues with the lead screws (they were replaced and the issue persisted), but instead the scintillator cage was catching on the stage as it was moving underneath and causing the issues. I had the cage replaced, the stage recalibrated and it's working perfectly once again.

Very glad to hear it.

The hardest thing running an instrument sometimes is trying to figure out whether the problem we're seeing is a hardware (or electronic), software (or firmware) issue!