9
95-8714
6.3
Table 5—LS2000 Receiver Fault Conditions (Continued)
Status
Condition
Recommended Action
4-20 Fault
(Open Loop)
The 4-20 mA output loop is not functioning
properly; the output mA level does not
match the output set point of the device.
Check field wiring, termination points, and resistance
of the 4-20 mA loop. Ensure that the 4-20 mA output
terminal of the LS2000 Receiver is connected to
ground through an appropriate sized load (see
instruction manual for details).
RAM Fault
System RAM test failed.
Cycle power to the unit. (If problem does not clear,
return to factory.)
Data Flash
Fault
Data can no longer be read/written to flash
memory inside the processor.
Cycle power to the unit. (If problem does not clear,
return to factory.)
Flash CRC
Fault
Non-Volatile Memory Operation Failed.
Cycle power to the unit. (If problem does not clear,
return to factory.)
AFE Fault
Receiver gain circuit failed.
Cycle power to the unit. (If problem does not clear,
return to factory.)
Internal
Voltage Fault
Internal step-down power supply out of
range condition.
Cycle power to the unit. (If problem does not clear,
return to factory.)
Active Signal
Saturated
Active sensor is receiving too much light
intensity from transmitter.
1. For installation with module separation distances
between 5 and 40 meters, the range reduction
aperture kit (supplied) is required.
2. Transmitter lamp voltage should be lowered to
reduce signal to receiver.
Ref. Signal
Saturated
Reference sensor is receiving too much
light intensity from transmitter.
1. For installation with module separation distances
between 5 and 40 meters, the range reduction
aperture kit (supplied) is required.
2. Transmitter lamp voltage should be lowered to
reduce signal to receiver.
Low Voltage Supply voltage to LS2000 is less than 16V. Supply voltage needs to rise above 16V. Check
supply voltage and power wiring.
High Voltage Supply voltage to LS2000 is greater than
33V.
Supply voltage needs to drop below 33V. Check
supply voltage and power wiring.
Heater Fault Heater is not working.
Fault will clear if heater is configured to be off. If
heater is required, return to factory for repair.
Broken Link If communication link is being used,
communication has been lost between
receiver and transmitter. (Annunciation of
this status condition is configurable and is
disabled by default.)
Check field wiring and ensure that the Rx/TX
communication link lines are connected as specified
in the instruction manual. Return unit to factory if
problem persists.
Failed Zero
Calibration
This fault will persist through power cycle
until a successful calibration is completed;
calibration will time out at 10 minutes
If the calibration process is allowed to time out, the
fault is set and can only be reset with a successful
calibration.
Calibrate
Active
at Startup
Zero calibration line is pulled low during
power up, resulting in a Zero Calibration
active during power-up.
1. Check receiver wiring to verify any wired
connection to terminal 6 (Reset/Cal) is not connected
to ground.
2. Upon power-up of the unit, make sure a magnet
is not positioned very close to the receiver bulkhead
area where magnetic switch resides.
Beam Block The receiver doesn’t see the light signal
from the transmitter continuously for 1
minute or the time set by user (Min 1
minute, Max 6 hours, default 1 minute)
1. Clear beam obstruction.
2. Check alignment and re-align if necessary.
Low Signal Indicated when the received light intensity
is below 30% of full scale at gain 100
1. Clean windows of receiver and transmitter.
2. Check alignment and re-align if necessary.
Negative Drift
–9% of Scale
A constant under range condition where
the gas reading is at or below –10% of full
scale reading for a period of one minute or
more. (Gas detection is still enabled, but
output reading will be lower than actual
gas concentration applied.)
1. Zero calibration in clean air environment.
2. Dense fog may be in beam path.
Over Range Overange condition is indicated by
a steady 20.5 mA output, as this is
maximum gas concentration that will be
displayed.
Gas is likely present in high concentration; react
accordingly.