Figure 5: SA bus terminal block wiring
Note:
The SA PWR terminal supplies 15 VDC. The SA
PWR terminal can be used to connect (daisy chain)
the 15 VDC power leads on the SA bus.
FC bus port
The FC bus port on the front of the controller is an RJ-12,
6-position modular jack that provides a connection for
the Wireless Commissioning Converter, or ZFR/ZFR Pro
Wireless Field Bus Router.
The FC bus port is connected internally to the FC bus
terminal block. See Table 5 for more information. The FC
bus Port pin assignment is shown in Figure 6.
Figure 6: Pin number assignments for sensor, FC Bus,
and SA bus ports on controllers
SA Bus port
The Sensor (SA Bus) port on the bottom of the controller
is an RJ-12, 6-position modular jack that provides a
connection for the Wireless Commissioning Converter, the
VAV Balancing Tool, specified network sensors, or other
SA Bus devices with RJ-12 plugs.
When the FEC is configured for N2 communication, the SA
Bus port must be used to download and commission the
controller. A DIS1710 Local Controller Display also can be
connected to the SA Bus port (but only on models without
integral display and push buttons).
The Sensor port is connected internally to the SA bus
terminal block. See Table 5 for more information. The
Sensor Port pin assignment is shown in Figure 6.
Supply power terminal block
The 24 VAC supply power terminal block is a gray,
removable, 3-terminal plug that fits into a board-mounted
jack on the top right of the controller.
Wire the 24 VAC supply power wires from the transformer
to the HOT and COM terminals on the terminal plug
as shown below. The middle terminal on the supply
power terminal block is not used. See Table 5 for more
information about the Supply Terminal Block.
Figure 7: 24 VAC supply power terminal block wiring
Note:
The supply power wire colors may be different
on transformers from other manufacturers. Refer to
the transformer manufacturer’s instructions and the
project installation drawings for wiring details.
Important:
Connect 24 VAC supply power to
the controller and all other network devices so
that transformer phasing is uniform across the
network devices. Powering network devices with
uniform 24 VAC supply power phasing reduces
noise, interference, and ground loop problems.
The controller does not require an earth ground
connection.
Wireless network applications
The controller can also be installed in a wireless
application using a ZFR/ZFR Pro Wireless Field Bus Router.
FEC26 Field Equipment Controllers Installation Guide
6
