WIKA T32.xS - Manual (Page 10)

GB
10
11583631.03 08/2014 GB/D/F/E
WIKA safety manual temperature transmitter T32.xS
2.4 Error signaling
The model T32.xS temperature transmitter monitors the connected sensor and its own
hardware for errors. In the event of a known error condition the instrument generates an
error signalling current.
The response time to the sensor error is a maximum of 90 seconds.
This implies the discovery of the following potential errors:
■ Sensor break
■ Sensor short-circuit (only for resistance temperature sensors, not for thermocouples)
■ Inadmissibly high lead resistance (not with resistance temperature sensors with
2-wire connection)
The online diagnosis test interval of the instrument should be a maximum of 35 minutes.
This implies the discovery of the following potential instrument errors:
■ ROM error
■ EEPROM error
■ RAM error
■ Program-counter error
■ Stack-pointer error
Furthermore, the following monitoring functions are carried out continuously:
■ Logical program flow control
■ Internal communication errors
■ Over sensor upper limit
■ Under sensor lower limit
■ Cold junction temperature outside permissible limits (only for thermocouples)
■ Duplex sensor drift monitoring (activated optionally)
■ Configuration error
■ Monitoring of the permissible instrument temperature (optional, activated by default
for SIL versions)
■ Monitoring of the output limits (optional, with SIL versions from 01 January 2011 not
activated as default)
CAUTION!
The instrument's error signalling current (error current) is configured in
accordance with the following requirements:
■ Error current, fail high (high alarm value):
settable in the range ≥ 21.0 mA to ≤ 23.0 mA (upscale)
■ Error current, fail low (low alarm value):
settable in the range ≥ 3.5 mA to ≤ 3.6 mA (downscale)
2. Safety