Honeywell SLG 700 User Manual page 79

Name (DTM/DD)
Unreliable Sensor
Communication
PV Out of Range
Fixed Current Mode
Low Supply Voltage
(DAC)
Device Variable Out Of
Range
Tamper Alarm
Sensor in Sleep Mode
Loop Current Noise
AO Saturated
Revision 5
Description (Cause)
Communication between sensor and
communication modules is not proper
due to damaged connector or
hardware issue with Comm module or
sensor module
PV value is not within LRV and URV
Output current is fixed and not
varying as per input.
Loop current mode is disabled or
Loop Test is active.
This is information to user.
Incorrect supply voltage at the
transmitter terminals.
User can notice this alarm if the
distance to the interface is bad but
device variable selected as PV is
derived from distance to product
which is valid.
The Tamper Alarm is set if more than
a specified number of attempted or
actual configuration changes are
made, when Tamper Alarm is
Enabled ( Device can be either Write
Protected or not ). The warning stays
active until the specified latency
period has elapsed.
Sensor in Sleep Mode due to
Configuration Change.
Sensor module adjusting model
parameters and waiting for sufficient
power to measure level.
DAC Not able to regulate loop
current. If this condition is observed
frequently, it could be an early
indication of critical under or over-
current failure.
Calculated analog output is either
above or below the specified loop
current limits (LRV and URV).
SLG 700 Series HART Option User's Manual
Resolution (Steps to take)
Verify the cable/connector between
communication and Sensor housing to
ensure that it is not damaged.
Either the transmitter is installed in a
noisy environment or internal
communication quality between the
Electronics Module and Sensor is
degrading. Try replacing either
Communication module or Sensor
housing.
Check if digital value of PV is out of
configured LRV and URV.
Read the echo curve to see if stem
markers are valid for distance to
product and distance to interface (if
applicable based on measured product
type).
If PV selected is derived from either
strapping table or Linearization table,
check the tables for valid entries.
Enable loop current mode if it is
disabled or exit the Loop Test mode if
active
Check the power supply and loop
resistance are within specification or
not. If they are correct, then replace the
terminal block assembly.
Read the Echo curve and verify valid
stem markers for distance to interface,
and configure the correlation algorithm
parameters for interface peak
reflections.
See page 30 for Tamper Alarm
configuration.
Power cycle the device and if problem
persist for more than 4 minutes replace
the Sensor housing
Try to find the source of the noise. It
could be bad loop wires, a hardware
problem inside the transmitter, loop
wires running close to a noise source
etc. If the environment is ok, replace the
Electronics Module.
Verify that the LRV and URV values are
in specified range or not.
Check if distance to product or distance
to interface is in blocking zones.
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