MKS 651D Series, User Manual, Page: 139 / 162

Chapter Seven: Maintenance and Troubleshooting Troubleshooting
127
How To Respond to a Checksum Error
A checksum error message indicates the controller has detected a calibration problem. The
controller sends a checksum error message in the following circumstances:
•
at system power up
•
in response to the R52 checksum command (1 = error).
If the controller detects a checksum error, perform a full calibration to correct the problem.
To perform a full calibration:
1. Calibrate the span of the A/D converter.
Refer to How To Calibrate the Span of the A/D Converter , page 128.
2. Zero the analog set point.
Refer to How To Zero the Analog Set Point , page 102.
3. Calibrate the full scale of the analog set point.
Refer to How To Calibrate the Full Scale of the Analog Set Point , page 103.
If the checksum error persists after you perform a full calibration, the error indicates a hardware
failure of the EEPROM. Contact any MKS Service Center, listed on the inside back cover of this
manual, for assistance.