28 • MRLDS-250 Infrared Gas Detector I&O Manual
026-1315 Rev 4
IMPORTANT: Fault
F.-15
may be caused by rapid
changes in temperature and other environmental
effects. If the
F.-15
fault remains after the ambient
temperature has stabilized, perform a manual re-zero
to clear the fault. See
Section 4.3., Perform a Manual
Zero
.
8.2.
Diagnostic Attributes
(P.-18)
Use this option to review the built-in diagnostic
attributes. Access the parameter list (see
Section 5,
Configure the Gas Detector
) and select
P.-18
. Press
the Enter button to access the diagnostics, and then
use the UP or DOWN button to select each attribute.
The following information is available.
MODBUS
Fault
0x00
20
MODBUS
message was
truncated or
timed out
early.
PPM
Overrange
Fault
0x00
40
PPM exceeds
9999. This
may indicate
a gross (very
large) leak. If
no leak is
present, it
indicates a
gas detector
error.
Input
Voltage
Fault
0x00
80
Input supply
power to the
MRLDS-250
is out of
range (i.e.,
24V ±20%).
IMPORTA
NT
: If this
fault is
active, the
gas detector
is offline and
not
monitoring.
Correct the
input supply
voltage to
restore
normal
operation.
Critical
Faults
Critical fault.
Cycle power
to the sensor
and see of the
fault clears.
If not,
contact
Emerson
technical
support for
additional
guidance.
:
:
Description
Fault
Code
Hex
Code
Possible
Causes
Table 8-1
- Fault Codes
Attribute
Description
Displays the current fault
condition code in hex format:
0000 = no faults are active
XXXX = HEX number
See
Table 8-1
for the HEX
format cross reference.
Displays a hex format code
that corresponds to any faults
that occurred since the
internal fault record was last
erased. See
Table 8-1
for the
HEX format cross reference.
The records may be erased
by pressing the ENTER
button.
Displays the number of days
that the MRLDS-250 has
been in service. The value of
this attribute rolls over after
9999.
Table 8-2
- Diagnostics Attributes