Engineering Index
Keyword Document
Comprehensive description of all LWS keywords
Mechanism Calibration
There are 5 mechanisms in LWS controlled by stepper motors in an open loop control system. Open loop control has no positional feedback thus position knowledge is determined by counting number of motor steps following a home sequence. The homing sequence must occur after each motor controller power cycle. The mechanisms have slightly different characteristics from one thermal cycyle to the next and do not home or initialize in excactly the same place. For the reason, a mechanism calibration procedure must be followed to optimize the perfromance of the instrument. Go to the Mechanism Calibration Procedure for a step by step instruction in the process.

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Last modified: Fri Jul 19 16:52:24 HST 2002