LAE

MR28-LH

MR Series • Refrigeration Controller

Type Refrigeration

Application Rack System

Probe Inputs 4

Relay Outputs 8

Communication RS485 Modbus RTU

Panel Size 96x96 mm

R1 Comp1

R2 Comp2

R3 Comp3

R4 Comp4

R5 Unloader1

R6 Unloader2

R7 Fan

R8 Alarm

Multi-compressor rack controller with up to 8 compressors

Technical Specifications

Display Type	LCD
Display Digits	4
Buttons	6
LED Indicators	Comp1, Comp2, Comp3, Comp4, Alarm, Network

Relay Outputs	8
Relay Rating	8A/250VAC

Operating Temp	-10 to 55°C
Storage Temp	-25 to 65°C

Terminal	Function	Type	Wire Color
1-2	Power 230VAC	Input	brown/blue
3-4	Suction Pressure 4-20mA	Input	red/black
5-6	Discharge Pressure 4-20mA	Input	yellow/black
7-8	Oil Pressure	Input	green/black
9-10	Temperature Probe	Input	orange/white
11-12	RS485 A+/B-	Comm	orange/yellow
13-14	Compressor 1	Output	black
15-16	Compressor 2	Output	black
17-18	Compressor 3	Output	black
19-20	Compressor 4	Output	black
21-22	Unloader/Comp5	Output	gray
23-24	Unloader/Comp6	Output	gray
25-26	Condenser Fan	Output	blue
27-28	Alarm	Output	red

Important: Always disconnect power before wiring. Verify terminal numbers with the actual controller label before connecting.

Code	Parameter	Range	Default	Description
SP	Pressure Setpoint	0 to 30	4 bar	Suction pressure setpoint
dP	Differential	0.1 to 5	0.5 bar	Compressor staging differential
ST	Stage Time	30 to 600	120 sec	Minimum time between stages
NC	Number of Comp	1 to 8	4	Number of compressors
RL	Rotation Logic	0=FIFO,1=Runtime	1	Compressor rotation method
HP	HP Cutout	10 to 35	28 bar	High pressure cutout
LP	LP Cutout	-1 to 5	0 bar	Low pressure cutout