The amp/check/divide board detected a W-axis counter fault. Possible causes are:
The gratings are dirty.
There is too much DC offset.
There is not sufficient amplitude in the read head signals.
The read head skew angle is improper.
The axis is moving too fast (rotary table is moving faster than 48 in/sec).
What you should do:
To clear the error, click Clear error in the XYZ Display window.
To clear it using an RCU-II, press and hold down the Servo Power Off button and then press the Joy button twice.
Clean the gratings using a soft, lint-free cloth and isopropyl or denatured alcohol.
Check to make sure the DC offset, amplitude, read head skew, and axis speed are within allowable limits.
If the error reoccurs, contact your Giddings & Lewis service representative.