Detcon DM-700 User Manual
Page 29
Model DM-700
DM-700 Instruction Manual
Rev. 4.0
Page 25 of 48
Clearing Fault - AutoSpan
If the sensor fails the signal stability criteria (Section 3.4.2) during AutoSpan sequence, the “Clearing Fault”
will be declared. A “Clearing Fault” will cause a “Fault Detected” message to flash intermittently on the ITM
display and drop the mA output to 0 mA. The Modbus™ fault register bit for Clearing Fault will be set and
will not clear until the fault condition has been cleared. The sensor should be considered as ‘Out-of-Service’
until a successful AutoSpan calibration is performed.
Zero Fault
If the sensor drifts to < -10% of range, an “Under-Range Fault” will be declared. An “Under-Range Fault”
will cause a “Fault Detected” message to flash intermittently on the ITM display. The Modbus™ fault register
bit for Under-Range Fault will be set and will not clear until the fault condition has been cleared. If an Under-
Range Fault occurs, the 4-20 mA signal will be set at 0mA until the fault condition is resolved.
Sensor Fault
If the intelligent plug-in sensor is not plugged in, plugged in incorrectly, or there is a communication failure, a
“Sensor Fault” is declared. A “Sensor Fault” will cause a “Fault Detected” message to flash intermittently on
the ITM display. The Modbus™ fault register bit for Sensor Fault will be set and will not clear until the fault
condition has been cleared. If a Sensor Fault occurs, the 4-20mA signal will be set at 0mA until the fault
condition is resolved.
Processor Fault
If the detector has any unrecoverable run-time errors, a “Processor Fault” is declared. A “Processor Fault”
will cause a “Fault Detected” message to flash intermittently on the ITM display. The Modbus™ fault register
bit for Processor Fault will be set and will not clear until the fault condition has been cleared. If a Processor
Fault occurs, the 4-20 mA signal will be set at 0mA until the fault condition is resolved.
Memory Fault
If the detector has a failure in saving new data to memory, a “Memory Fault” is declared. A “Memory Fault”
will cause the “Fault Detected” message to flash intermittently on the ITM display. The Modbus™ fault
register bit for Memory Fault will be set and will not clear until the fault condition has been cleared. If a
Memory Fault occurs, the 4-20mA signal will be set at 0mA until the fault condition is resolved.
4-20 mA Loop Fault
If the sensor detects a condition where the 4-20mA output loop is not functional (high loop resistance or failed
circuit function) a “4-20mA Fault” is declared. A “4-20mA Fault” will cause the “Fault Detected” message to
scroll once a minute on the ITM display. The Modbus™ fault register bit for Loop Fault will be set and will
not clear until the fault condition has been cleared. If a Loop Fault occurs, the 4-20mA signal will be set at
0mA until the fault condition is resolved. If the 4-20mA current loop is still out of tolerance, contact Detcon
at
, or contact Detcon customer service.
Input Voltage Fault
If the detector is currently receiving an input voltage that is outside of the 11.5-28VDC range, an “Input
Voltage Fault” is declared.
An “Input Voltage Fault” will cause the “Fault Detected” message to flash
intermittently on the ITM display. The fault register bit for Input Voltage Fault will be set and will not clear
until the fault condition has been cleared. If an Input Voltage Fault occurs, the 4-20mA signal will be set at
0mA until the fault condition is resolved.