Home Forums General Discussion Technical Questions 211 CHC issues

Hello,
I have a duplex 211 that goes on CHC after a quick power outage. I don't have UPS and E-power. Thesedevices have been running for over 15ys but since the last 2ys, these service calls have been more frequant. i have to force the I/O back to 0.
Any idea why this would happen? Thank you.

CHCS input is active low, i.e. when no voltage is on the input, CHCS will be in upper case on the service tool’s monitor inputs screen. You might want to check whatever power supply is feeding the CHCS switch or its remote station. It seems that it’s not recovering after the “quick” power outage.

How do you define “quick” ?

How are you forcing the I/O back to 0? Are you setting its RSL address to 00-0 and then setting it back to the address and pin it was originally set to?

Copy your EEPROM to a new blank chip. Your existing chip is corrupt.