Figure 7: 24 VAC supply power spade terminal wiring
Important:
• The supply power terminal block on the FX18-PCV is a two-position spade lug (Figure 7).
Exercise caution while rewiring the power plug when replacing an existing controller. Stray
wire strands may make contact and cause a short circuit across the 24 VAC power supply.
• To maintain proper phasing when replacing the existing PCV14xx controller with the FX-
PCV18 controller, connect the power wire from 24 VAC: 1 terminal on the existing controller
to the HOT power terminal on the FX-PCV18. Also connect the power wire from the 24 VAC: 2
terminal on the existing controller to the COM power terminal on the FX-PCV18 controller.
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 FX-PCV 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 FX-PCV does not require an earth ground connection. However, when grounding the
secondary of the 24 VAC transformer is required, only one connection to ground should be
made near the transformer.
CAUTION
Risk of Personal Injury and Property Damage
Improper wiring of this terminal may cause a short circuit across the 24 VAC power supply on -1
models.
To wire the FX-PCV18 Series controller, complete the following steps:
1. Terminate wiring per engineering drawings.
2. Wire network sensors and other devices to the FX-PCV's SA Bus.
3. Wire the N2/FC Bus in a daisy chain (see Table 6).
4. Ensure that the FX-PCV’s device address DIP switches are set to the appropriate device address.
5. Connect the FX-PCV controller to 24 VAC, Class 2 power.
Refer to the
N2 FX-PCV Application Note (LIT-12011838)
for more information about replacing an
existing controller with an FX-PCV18 controller.
9
FX-PCV1826/1832 Programmable VAV Box Controller Installation Instructions