
BAC-7001 and BAC-7051 VAV controllers 3 Installation Guide
Connecting an airflow sensor
An airow sensor is incorporated as one of the
inputs to the controller. Remove the plugs and
connect the tubing from the pitot assembly to the
airow sensor inputs above the drive hub.
Mount the controller close enough to the pitot tubes
to keep the tubing length to be less than 24 inches
between the controller’s inputs and the tubes.
Connecting to an MS/TP network
BAC‑7000 series VAV controllers BACnet MS/
TP compliant controllers. Connect them only
to a BACnet MS/TP network. 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 trac bolenecks, 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.
Connect a KMD–5575 BACnet MS/TP repeater
between every 32 MS/TP devices or if the cable
length will exceed 4000 feet (1220 meters). Use
no more than four repeaters per MS/TP network.
Place a KMD–5567 surge suppressor in the cable
where it exits from a building.
On the controllers at the physical ends of the
EIA‑485 wiring segment, set the end‑of‑line
termination to On using the EOL switches.
See Application Note AN0404A, Planning BACnet
Networks for additional information about installing
controllers.
Connecting power
The controllers require an external, 24 volt, AC
power source. Use the following guidelines when
choosing and wiring transformers.
Use a KMC Controls Class–2 transformer of
the appropriate size to supply power to the
controllers.
KMC Controls recommends powering only one
controller from each transformer.
Do not run 24 volt, AC power from within an
enclosure to external controllers.
Connect the 24 volt AC power supply to the
power terminal block on the lower right side of
the controller near the power jumper. Connect the
ground side of the transformer to the – terminal
and the AC phase to the ~ (phase) terminal. Power
is applied to the controller when the transformer
is connected to power and the power jumper is in
place.
S
+B
-A
S
+B
-A
S
+B
-A
Illustration 3—MS/TP network wiring
Set the EOL
switches to On for
these controllers.