Hello,
I once had a defective auto-sampler, and in the process of finally determining that the teeth on the
belt had broken, which was why the arm was leaving vials intermittently in the tower, and then trying
to put a new vial on top if it. (not your symptoms I realise)
I realised that there were two movements, that produced three different error codes.
and all rely upon the micro-switch on the gripper.
1) If there was no vial in the tray, then the error message was eg ''No Vial found'' or something similar
2) If there was a vial in the tray, and the gripper locked onto it, but lost it when it was lifting up,
then the error message was something along the lines of ''lost from gripper'' or something similar
3) If there was a vial in the tray, and it had picked it up, and was rotating it to the tower, but lost it
whilst the arm was rotating then the error message was eg ''bottle lost in move'' or something similar
As the only sensor that the autosampler has, is the microswitch in the gripper, that could be a place to look.
As I was using a 3396a integrator, the error messages may be different.
One test to try, is to set the sequence to pick a vial in position 100, but instead of a vial,
have the flat end of a pen where the vial cap is usually located, so when it goes to pick up the vial,
it will think there is a vial there, put loses it when it is picking it up, and see if the error message is different,
as it may be an alignment issue, in that the gripper does not go low enough (eg cogs slip
on broken belt teeth), so it is only gripping around the top tip of the vial cap, but still low enough to
active the micro-switch.
Or, there is a bad/broken connection with the micro-switch/wiring, and the vibration during movement causes
it to trip the controller, and post your error
p.s. You can also try setting up a digital camera in movie mode, to record the sequence and see if you
can spot anything odd, if it is an intermittent problem.
p.p.s. If it is the teeth on the belt, I think what I did was shift the belt to a new position, as I don't
seem to recall buying a new belt.
Alex
