Table 2: Bottom wiring terminal blocks, terminals, and wire sizes
Terminal
number
MR534
Terminal
block
label
Terminal Description, function, and
requirements
Required wire size
14
L1
15
120–240
VAC
L2
Line-voltage supply power
terminals for the controller. See
the Supply power row in Table 35
0.75 mm
2
to 2.5 mm
2
(18 AWG to 14 AWG)
16
LC
Line COM Line-voltage common relay
terminal. Defrost and compressor
relays share the LC terminal line
voltage source. See Table 30 and
Table 33 for electrical ratings.
17
LNO
Def
Defrost heater relay line voltage
output terminal. See Table 33 for
electrical ratings.
18
LNO
Comp
Compressor relay line voltage
output terminal. See Table 30 for
electrical ratings.
1.5 mm
2
to 2.5 mm
2
(16 AWG to 14 AWG)
19
C
Common terminal for BI
20
BI1
21
BI
BI2
Open or closed state detection.
Dry contact switch.
Note:
Do not apply any
voltage to BI terminals 19, 20,
and 21. Connect only user-
supplied dry contact switches
to these terminals.
0.34 mm
2
to 1.5 mm
2
(22 AWG to 16 AWG)
stranded wires and twisted-
leads cable.
Cleaning the controller UI
Before you begin:
Remove the protective plastic film from the controller’s display after installation.
Note:
• Do not use abrasive cleaning powders.
• Do not use abrasive cleaning pads or brushes.
• Do not use solvents or cleaning solutions that can damage plastic.
1. Disconnect all power sources to the controller.
2. Remove any loose debris from the controller and use a slightly damp soft cloth with a warm,
mild, detergent solution to wipe the exterior surface.
3. Rinse the cloth with clean water and wipe the controller with a clean and slightly damp cloth
until it is clean.
4. Dry the controller with a soft cloth.
9
MR5 Series Panel Mount Case Controller Technical Bulletin
Discontinued
