Precision Digital PD138 - Manual (Page 15)

PD138 Minimux
®
II Temp & Process Scanner Instruction Manual
15
MULTIPLE PD138 CONNECTIONS
Multiple Minimux
®
II can be connected together to increase multiplexing
capacity for an unlimited number of points. When connecting several
units together, one unit of the group is designated the master unit and all
other units function as follower units. Multiple unit configuration is simply
done by connecting the units together as shown below. The system will
self-determine if there are two or more Minimux
®
II connected together.
No special cable is needed to connect multiple PD138s together.
There are three connections that must be made to connect multiple
PD138s into a system:
1. Master/Follower Connections
2. Multiplexer Output Signal Connections
The inputs to each unit are connected as for single units. The outputs of
all Minimux® II (terminals output A, output B, and TP) are connected in
parallel and then connected to the display meter.
Notes:
1. Use thermocouple wire when interconnecting a thermocouple system.
2. Terminals TP are only used in a three-wire RTD application.