Ametek Thermox CEM O2/TM, User Manual

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Controller / User Interface | 4-33
Service Alarm
The service alarm operates as normally closed (service alarm condi-
tion causes open contacts).
The service alarm provides an alarm that alerts you of possible system
problems that require attention. Events that can trigger the service alarm
to activate are as follows:

Error condition (detected by software)

System operational variance (such as an over-temperature or under-
temperature condition)

Calibration failure

Verification failure

Control unit power failure
Watchdog Relay
During normal system operation, the watchdog relay operates as
normally closed (system failure causes open contacts).
The watchdog alarm relay de-energizes when the system watchdog timer
times out. The watchdog timer will time out and cause the control unit to
reset itself to prevent the control unit from becoming “lost” due to such
things as noise spikes or power surges. You can use this relay to activate a
remote indicator to notify you if the watchdog timer times out.
In addition, the control unit reads the watchdog after reset, and beeps for
a brief time if the reset was caused by a watchdog condition. Pressing the
reset keys simultaneously (hidden keys to the left and right of the Setup
Key) for a long enough time will in turn cause a watchdog, which will
indicate as a beep after the system restarts upon release of the reset keys.
NOTE
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NOTE
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