RayTek MI Miniature Infrared Sensor - Manual (Page 69)

Maintenance
MI 61
9.2 Fail‐Safe Operation
The Fail‐Safe system is designed to alert the operator and provide a
safe output in case of any system failure. The sensor is designed to
shutdown the process in the event of a set‐up error, system error, or a
failure in the sensor electronics.
The Fail‐Safe circuit should never be relied on
exclusively to protect critical processes. Other safety
devices should also be used to supplement this function!
When an error or failure does occur, the display indicates the
possible failure area, and the output circuits automatically adjust to
their preset levels, see the following tables.
Error Codes for the Outputs
Symptom mV 0 to 20 mA 4 to 20 mA TC-K TC-J
Temperature over
range 5 V 21 mA 21 mA - -
Temperature under
range 0 V 0 mA 2.5 mA - -
Defect of the internal
head ambient
temperature probe 5 V 21 mA 21 mA > 1200°C
(2192 °F) > 1200°C
(2192 °F)
Table 7: Error Codes (Outputs)