17
95-8676
3.1
FAULT INDICATION
There are three modes of signaling faults using the
4-20 mA analog signal output:
• Eclipse (Factory default setting)
• User Defined
• PIR9400
Fault signaling mode can be selected using the HART or
MODBUS interface. Table 3 shows the current levels for
each fault mode.
Eclipse Fault Mode
Eclipse mode follows conventional fault signaling
practice. The current loop output indicates the
presence of a fault, but does not attempt to identify
a specific fault with a specific current output value.
Identification of a specific fault type is done through
the HART Communicator or MODBUS.
User Defined Fault Mode
This mode is intended for users who wish to program
unique current levels for faults and calibration signals.
User defined current levels can be set from 0.0 to 24.0
mA. and can be programmed from HART or MODBUS
interfaces. Four unique current levels are available:
warm-up, general fault, calibration, and blocked optics.
PIR9400 Fault Mode
PIR9400 mode is provided for compatibility with existing
Det-Tronics PointWatch gas detectors. When using the
Eclipse CO
2
detector, this mode is
not recommended
because HART communication will be lost when the
milliamp signal goes below 1 mA.
Table 3—Output Levels of 4-20 mA Current Loop and Corresponding Status Indications
Condition
Eclipse Fault Mode
User Defined Fault Mode
PIR9400 Fault Mode
(Not Recommended)
Gas Level (-10% to 120% Full scale)
2.4 to 20.5
2.4 to 20.5
2.4 to 20.5
Warm-up
1.00
Warm-up
0.00
Reference Sensor Saturated
1.00
General Fault
0.20
Active Sensor Saturated
1.00
General Fault
0.40
Calibration line active on power-up
1.00
General Fault
0.60
Low 24 volts
1.00
General Fault
0.80
Low 12 volts
1.00
General Fault
1.20
Low 5 volts
1.00
General Fault
1.20
Dirty Optics
2.00
Blocked Optics
1.00
Calibration Fault
1.00
General Fault
1.60
Calibration complete
1.00
Calibration
1.80
Span calibration, apply gas
1.00
Calibration
2.00
Zero calibration in progress
1.00
Calibration
2.20
Negative signal output fault
1.00
General Fault
2.40
Flash CRC
1.00
General Fault
1.20
Ram Error
1.00
General Fault
1.20
EEPROM Error
1.00
General Fault
1.20
IR Source Failure
1.00
General Fault
1.20
