Service manual
Service Manual SM-MDS_(i)      31 
4.4 Wiring Connection 
MC501 gateway acts as a bridge in converting and transmitting signals and allows communication between 
computer and MDS system. The wiring connection is basically divided into two sections: 
a) Wiring connection between outdoor and gateway (length must <1000m between last outdoor and gateway) 
b) Wiring connection between gateway and computer (length must <2m) 
For wiring connection between outdoor and gateway, the communication cable is directly connected from 
outdoor terminal to the gateway, where A
pc
 and B
pc
 (from outdoor) connect to A1 and B1 (on MC501 gateway) 
respectively. For certain models, the outdoor terminal will be labeled with numbers instead of A
pc
 and B
pc
. The 
corresponding numbers for A
pc
 and B
pc
 are as follow: 
R22 Model  Terminal Number for A
pc
  Terminal Number for B
pc
MDS80/100/120/150/260/280/300/320B/BR 32  33 
MDS180/200/220/240B/BR 47 48 
R410A Model  Terminal Number for A
pc
  Terminal Number for B
pc
5MDS80/100/120/140/160/180/260/280/300/320/340/360B/BR 32  33 
5MDS200/220/240/380/400/420/440/460/480/500B/BR 47  48 
The wiring connection between MC501 gateway and MDS system is as follow: 
Wiring connection from MC501 Gateway to MDOM PCB 
Wiring connection from MC501 Gateway to MDS-M PCB 
MC501 
Gatewa
y
First Outdoor with MDOM PCB 
Earth the 
screen wire 
Computer with 
Smart 
Commander 
Bpc Apc 
Outdoor with 
MDS-M PCB 
Computer 
with Smart 
Commander
Earth the 
screen wire 
Ap
c B
p
c
4 










