Watlow EZ-ZONE ST - Manual (Page 81)

Watlow EZ-ZONE ® ST • 79 • Appendix
Chapter 8: Appendix
Troubleshooting
Indication Description Possible Cause(s) Corrective Action
Alarm won’t clear or
reset
Alarm will not clear or reset
with keypad or digital input
• Alarm latching is active
• Alarm set to incorrect output
• Alarm is set to incorrect source
• Sensor input is out of alarm set point
range
• Alarm set point is incorrect
• Alarm is set to incorrect type
• Digital input function is incorrect
• Reset alarm when process is within
range or disable latching.
• Set output to correct alarm source
instance.
• Set alarm source to correct input in-
stance.
• Correct cause of sensor input out of
alarm range.
• Set alarm set point to correct trip
point.
• Set alarm to correct type: process, de-
viation or power.
• Set digital input function and source
instance.
Alarm won’t occur Alarm will not activate output • Alarm silencing is active
• Alarm blocking is active
• Alarm is set to incorrect output
• Alarm is set to incorrect source
• Alarm set point is incorrect
• Alarm is set to incorrect type
• Disable alarm silencing, if required.
• Disable alarm blocking, if required.
• Set output to correct alarm source
instance.
• Set alarm source to correct input in-
stance.
• Set alarm set point to correct trip
point.
• Set alarm to correct type: process, de-
viation or power.
[AL`1] Alarm Error
[AL`2]
Alarm state cannot be deter-
mined due to lack of sensor
input
• Sensor improperly wired or open
• Incorrect setting of sensor type
• Calibration corrupt • Correct wiring or replace sensor.
• Match setting to sensor used.
• Check calibration of controller.
Sensor input below low alarm
set point
• Temperature is less than alarm set
point
• Alarm is set to latching and an alarm
occurred in the past
• Incorrect alarm set point
• Incorrect alarm source
• Check cause of under temperature.
• Clear latched alarm.
• Establish correct alarm set point.
• Set alarm source to proper setting.
Sensor input above high
alarm set point
• Temperature is greater than alarm
set point
• Alarm is set to latching and an alarm
occurred in the past
• Incorrect alarm set point
• Incorrect alarm source
• Check cause of over temperature.
• Clear latched alarm.
• Establish correct alarm set point.
• Set alarm source to proper setting.
[Er;i1] Error Input
[Er;i2]
Sensor does not provide a
valid signal to controller
• Sensor improperly wired or open
• Incorrect setting of sensor type
• Calibration corrupt • Correct wiring or replace sensor.
• Match setting to sensor used.
• Check calibration of controller.
Limit won’t clear or
reset
Limit will not clear or reset
with keypad or digital input
• Sensor input is out of limit set point
range
• Limit set point is incorrect
• Digital input function is incorrect
• Correct cause of sensor input out of
limit range.
• Set limit set point to correct trip point.
• Set digital input function and source
instance.
[LiM] Limit Error Limit state cannot be deter-
mined due to lack of sensor
input, limit will trip
• Sensor improperly wired or open
• Incorrect setting of sensor type
• Calibration corrupt • Correct wiring or replace sensor.
• Match setting to sensor used.
• Check calibration of controller.
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