Liebert MR1 사용자 설명서

Electrical Connections 

The MR1 Mini-Remote requires a two-wire connection (field-

supplied) to communicate with the Environmental unit under its 

control. The stranded twisted-pair connects to the MR1 interface 

board at TB2-11 (T+) and TB2-12 (T-).  Refer to Table 1 below 

for the connections at the Environmental unit.  Note that 

maximum length for RS-422 communications is 1000 feet, and 

minimum of 22 gauge wire should be used for all field wiring.

 

Power for the MR1 is supplied to TB3-1 and TB3-2. Maximum 

current draw is 0.3A at 24VAC.  It is recommended that the 

MR1 be powered independently from an external 24VAC 

transformer; optionally, it may draw power from the 

Environmental unit.  However, if the MR1 is located greater 

than 300 feet (100 meters) from the Environmental unit, an 

external transformer must be used.  

SM - Standard  

AM/AG - Advanced  

L10 - Level 10  

Microprocessors 

Terminal T5 
Terminal G5 

Terminal 78 (T+) 

Terminal 77 (T-) 

L00 - Level 00 

Microprocessor 

TB1-1 

TB1-5 

Terminal 78 (T+) 

Terminal 77 (T-) 

- 

TB4-1 (T+) 

TB4-2 (T-) 

SSC - Small System 

Controller 

- 

TB2-1 (T+) 

TB2-2 (T-) 

Table 1: Connection Summary 

The MR1 provides a Common Alarm Output, at TB2-9 and 

TB2-10.  This dry-contact is rated for 5A, at 24VDC or 

120VAC.  

There are four optional Customer Alarm inputs that may be used 

on the MR1 (see Hardware Configuration).  The inputs are 

triggered by contact-closures, and the contacts are rated for 5A, 

at 24VDC or 120VAC as well.  The connection points and 

display mapping are as follows: 

Local Alarm 1:  

TB2-3   &  TB2-4 

Local Alarm 2: 

TB2-1   &  TB2-2 

High Water Alarm:  TB2-5   &  TB2-6 

High Head Alarm:  TB2-7   &  TB2-8 

 

Liebert MR1 • 5