16 • MRLDS-250 Infrared Gas Detector I&O Manual
026-1315 Rev 4
Alarm Setpoint
Sets desired PPM value (range
75 to 3500 ppm) above which
alarm occurs. Use UP or
DOWN buttons. For faster
“coarse” adjustment, hold
either button to sweep through
the adjustment range quickly.
Default setpoint is 200 ppm
.
Analog Output Type
Selects output type:
00 Selects 0-5V
01 Selects 1-5V
(default)
02 Selects 0-10V
03 Selects 2-10V
04 Selects 4-20 mA
Alarm ON Delays
Sets the ON delay time (0-15
minutes) for the alarm output
signals (relay, Modbus).
The
default delay is 0 minutes
.
Alarm OFF Delays
Sets the OFF delay time for the
alarm output signals (relay,
Modbus) in minutes (0-15).
The default delay is 0
minutes
.
Relay Contact Behavior
(Failsafe Mode)
Sets the default relay power
state so that power loss can be
detected.
The behavior of the relay
changes from energizing when
an alarm condition occurs
(default) to energizing at power
up (Failsafe). In both cases the
relay changes state when an
alarm occurs, failsafe is simply
inverted. This allows power
failures to be detected as
alarms.
00 NO (default mode)
01 Failsafe mode
Parameter
Description
Table 5-2
- Parameter Numbers, Names, and
Descriptions
Relay Latching
Controls the relay latching
behavior.
00 OFF (default)
. Relay
does not latch, and resets once
the alarm condition is removed.
01 ON. Relay remains
latched; reset by BMS
command by pressing and
holding the Enter button for
five seconds.
Audible Alarm
The units have an internal
audible alarm. You can disable
this, but the default setting is
“enabled” in compliance with
EN378.
00 OFF
01 ON (default)
Display Mode
The display can be turned on by
using this parameter. When set
to ON the display never shuts
off (all operating modes). When
ON the display shows the
current gas concentration (or 0
if below the squelch). Note that
P.-09
is disabled if
P.-19=0
.
00 OFF during normal
operation when the ppm value
is below the alarm setpoint
(default)
01 ON
In either case, the display will
blink the measured PPM value
during an alarm state.
RS485 Node Address
Sets the RS485 node address
(0001 to 0255)
Parameter
Description
Table 5-2
- Parameter Numbers, Names, and
Descriptions