Restrictions; Mechanical Installation; Electrical Installation; Preparations - Emerson MRLDS-450 Installation And Operation Manual

3.2. Restrictions

The installation location must have appropriate supply power available for the
instrument (For example, 19.5 to 28.5VDC or 24VAC). This ultimately determines
the distance the instrument can be mounted from the controller or power supply.

3.3. Mechanical Installation

WARNING! DO NOT allow the lid/sensor to hang from the ribbon cable. Failure to
comply may result in damage to the product.
1. Using the provided hardware, securely mount the MRLDS-450 Gas Detector 
according to the product dimensions, maximum wiring lengths and following 
considerations:
a. Environment: the full range of environmental conditions when selecting a 
location.
b. Application: the specifics of the application (possible leaks, air movement/draft,
etc.) when selecting a location.
c. Accessibility: the degree of accessibility required for maintenance purposes
when selecting a location.
d. Target Gas: the specific gravity of the target gas when selecting the height of the
instrument.
2. Using a 5/32" (4mm) hex key/allen wrench (not included) remove the lid and 
disconnect the ribbon cable from the base.
3. Set the lid and rubber gasket aside to be reinstalled later.

3.4. Electrical Installation

3.4.1. Preparations

IMPORTANT: If analog output is configured for 4 to 20mA output, ensure that the current
loop is connected to a sinking current loop monitor before powering on the instrument.
Otherwise, a fault may be displayed indicating an open loop condition. If analog output is
unused, ensure it is configured as a voltage output (default: 1-5V) to prevent an open loop
fault condition. The analog output is designed as sourcing.
WARNING! Ensure wiring for relays and connections for sensor(s) are made before
applying power.
8 • MRLDS-450 Refrigerant Gas Detection I&O Manual


026-1316 Rev 0