Installation Instructions

Document No. 553-170
Installation Instructions
November 03, 2017
Siemens Industry, Inc. Page 3 of 4
Installation Instructions
WARNING:
Turn OFF AC power at the circuit breaker
panel.
CAUTION:
UL Listings require that NEC Class I and
Class II wiring be kept separate from each
other. Use separate conduit and cable tie
bars to separate Class I DO wires from all
other Class II wiring.
Securely fasten the PXC Compact so that it
does not come loose when point connectors
are removed.
If you need to reinsert one of the mounting
tabs, see the PXC Compact Series Owner’s
Manual (553-104) for instructions.
The PXC Compact may be mounted either vertically
(with 24 Vac and DOs on the right) or horizontally (with
24 Vac and DOs at the top).
Options for Mounting the PXC Compact
Select one of the following options for installation:
 Mount the controller on a DIN rail by using the
four slide-out mounting tabs.
 Fasten the controller to a surface or enclosure
backplane with screws
Option 1: Mounting the Controller on a DIN
Rail
To provide a minimum clearance for wiring,
allow 6 inches (15 cm) from the center of the
DIN rail to obstructions on either side.
Installing the DIN Rail
Do the following if the DIN rail is not already installed.
1. Align and level the DIN rail on the mounting surface
or the backplane of the enclosure.
2. Mark the position of the mounting holes at either end
of the DIN rail.
3. Using wall anchors, if necessary, attach the DIN rail
to the surface or the backplane.
For longer DIN rails, use one mounting
screw per running foot of DIN rail.
Installing the PXC Compact
1. Slide out the mounting tabs.
2. Align the channel on the back of the device with the
DIN rail.
3. Using a flat-blade screwdriver, push in each
mounting tab until it clips onto the DIN rail.
4. Continue with Completing the Installation.
Option 2: Fastening the Controller with
Screws
Allow a minimum clearance of 3 inches (7.6
cm) around the controller ports and
connectors for terminating wires.
1. Select one of the following options for fastening the
controller:
 Drive screws through the four slide-out
mounting tabs.
 Drive screws through the two mounting holes in
the controller cover and through two mounting
tabs at the opposite corners.
2. Slide out the required mounting tabs.
For installation in an enclosure backplane,
use the 3/8” self-tapping screws and, if
necessary, the 1-3/4” self-drilling screws.
For mounting on a surface, use the 3/4” self-
drilling screws and, if necessary, the 1-3/4”
self-drilling screws.
3. Align the PXC Compact on the mounting surface
and mark the position of the mounting holes.
4. For installation in an enclosure, align the mounting
holes of the PXC Compact with holes in the
perforated backplane.
5. If necessary, drill the mounting holes and insert wall
anchors.
6. Secure the controller using the provided screws.
7. Continue with Completing the Installation.