Marc Daniel

Today we checked on a voltage offset problem in the OPO ISS. This manifested itself with a control monitor readback that was several volts different from the drive point input, when the servo was off.

While hooking up the tester we noticed that the gain stages were cross wired through software. This required a TwinCAT fix and restart. Finally, we traced the voltage offset to a busted OmAmp in the ramp input. This device was replaced and the chassis is now working correctly.