BAC-7302 RTU Controller
Revision E
Installing the controller
Connecting to a NetSensor
11
Output 3
Typically programmed with a PID loop object to control two-stage
cooling. Triac 3A turns on when the programmed output is above 40% and off below
30%. Triac 3B turns on when the programmed output is above 80% and turns off
below 70%.
Output 4
This output is a universal output that can be programmed as either an
analog or digital object.
Connecting to a
NetSensor
The Network RJ–12 connector provides a connection port to a NetSensor model
KMD–1161 or KMD–1181. Link the controller to a NetSensor with a KMC Controls
approved cable up to 75 feet long. See the installation guide supplied with the
NetSensor for complete NetSensor installation instructions.
Connecting to an
MS/TP network
Connections and wiring
Use the following principles when connecting a controller to an MS/TP network:
◆
Connect no more than 128 addressable BACnet devices to one MS/TP network.
The devices can be any mix of controllers or routers.
◆
To prevent network traffic bottlenecks, limit the MS/TP network size to 60
controllers.
◆
Use 18 gauge, twisted pair, shielded cable with capacitance of no more than
50 picofarads per foot for all network wiring. Belden cable model #82760 meets
the cable requirements.
◆
Connect the -
A
terminal in parallel with all other - terminals.
◆
Connect the +
B
terminal in parallel with all other + terminals.
◆
Connect the shields of the cable together at each controller. For KMC BACnet
controllers use the
S
terminal.
◆
Connect the shield to an earth ground at one end only.
◆
Use a KMD–5575 repeater between every 32 MS/TP devices or if the cable
length will exceed 4000 feet (1220 meters). Use no more than seven repeaters
per MS/TP network.
◆
Place a KMD–5567 surge surpressor in the cable where it exits a building.
Illustration 2-3 Connection to a NetSensor
OUT4
GND
T3B
RTN3
T3A
T2B
RTN2
T2A
RT
N1
T1
75 feet Max.
