Figure 6: Pin number assignments for sensor, SA bus
and FC bus ports on expansion modules
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 expansion module.
Wire the 24 VAC supply power wires from the transformer
to the HOT and COM terminals on the terminal plug as
shown in Figure 7. The middle terminal on the supply
power terminal block is not used.
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
expansion module 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
expansion module does not require an earth ground
connection.
Wireless network applications
About this task:
The expansion module can also be installed in a wireless
application using a ZFR/ZFR Pro Wireless Field Bus Router.
To configure an expansion module for use with the ZFR/
ZFR Pro Series Wireless Field Bus system:
Note:
IOMs can communicate wirelessly on the FC
bus only.
1. Connect the ZFR181x or ZFR182x Wireless
Field Bus Router to the FC bus port (RJ-12
modular jack) on the front of the expansion
module.
2. Ensure that the expansion module's device
address DIP switches are set to the correct
device address. See .
3. Set DIP switch 128 to ON, which enables
wireless operation on the expansion module.
Result:
For more information on the ZFR Pro Wireless Field Bus
system, refer to the
WNC1800/ZFR182x Pro Series Wireless
Field Bus System Product Bulletin (LIT-12012320)
.
For more information on the ZFR 1800 Wireless Field
Bus system, refer to the
ZFR1800 Series Wireless Field Bus
System Product Bulletin (LIT-12011336)
.
Terminal Wiring Guidelines,
Functions, Ratings, and
Requirements
Input and output wiring guidelines
Table 2 provides information and guidelines about the
functions, ratings, and requirements for the expansion
module input and output terminals, and references
guidelines for determining proper wire sizes and cable
lengths.
In addition to the wiring guidelines in Table 2, observe
the following guidelines when wiring expansion module
inputs and outputs:
• Run
all
low-voltage wiring and cables separate from
high-voltage wiring.
• All input and output cables, regardless of wire size or
number of wires, should consist of stranded, insulated,
and twisted copper wires.
• Shielded cable is not required for input or output
cables.
• Shielded cable is recommended for input and output
cables that are exposed to high electromagnetic or
radio frequency noise.
• Inputs/outputs with cables less than 30 m (100 ft)
typically do not require an offset in the software setup.
Cable-runs over 30 m (100 ft) may require an offset in
the input/output software setup.
IOM2721 Input/Output Module Installation Guide
5