Liebert PX018 Installer's/User's Manual page 110

5) CANbus terminal connections – Field terminals for CANbus cable connection.
• 5A is the CANbus connectors.
o TB49-1 is the input terminal for CANbus high.
o TB49-3 is the input terminal for CANbus low.
o TB50-1 is output terminal for CANbus high.
o TB50-3 is the output terminal for CANbus low.
o Each CANbus cable shield is connected to terminal "SH", item 9.
• 5B is the "END OF LINE" jumper.
• 5C is the CANbus "DEVICE ADDRESS DIP SWITCH". CANbus cable not by Liebert. See Note 2. (below)
6) Remote unit shutdown – Replace existing jumper between terminals TB38-1 and TB38-2 with field supplied normally closed
switch having a minimum 75VA 24VAC rating. Use field supplied Class 1 wiring. (This is an optional feature that may be owner specified.)
7) Alarm terminal connections –
a. Common Alarm Relay indicates when any type of alarm occurs. TB74-1 is common, TB74-2 is normally open, and TB74-3 is
normally closed. 1 Amp 24VAC is the maximum load. Use Class 1 field supplied wiring.
b. Shutdown Alarm Relay indicates when condenser loses power, or when a critical alarm has occurred that shuts down the
condenser unit. TB74-4 is common, TB74-5 is normally open, and TB74-6 is normally closed. 1 Amp 24VAC is the maximum load.
Use Class 1 field supplied wiring.
8) Indoor unit interlock and SPD alarm terminals –
a. On any call for compressor operation, normally open contact is closed across terminals 70 and 71 for Circuit 1, and normally open
contact is closed across terminals 70 and 230 for Circuit 2 from indoor room unit.
b. During SPD alarm, normally open contact is closed across terminals 12 & 13. SPD is an optional device.
9) CANbus shield terminal – Terminal for field shield connection of the CANbus field supplied cables. The shield of CANbus field supplied
cables must not be connected to ground at the condenser.
10) Primary low voltage entrance – One 7/8" (22.2mm) diameter knockout that is free for customer low voltage wiring.
11) SPD entrance – One 7/8" (22.2mm) diameter knockout hole located at the bottom of the enclosure. High voltage surge protective device
(SPD) is optional.
NOTES:
1. Refer to specification sheet for unit voltage rating, full load amp, and wire size amp ratings.
2. The CANbus wiring is field supplied and must be:
- Braided shield or foil shield with drain wire
- Shield must be wired to ground at indoor unit
- 22-18AWG stranded tinned copper
- Twisted pair (minimum 4 twists per foot)
- Low Capacitance (15pF/FT or less)
- Must be rated to meet local codes and conditions
- EXAMPLES BELDEN 89207 (PLENUM RATED), OR ALPHA WIRE 6454 CATEGORY 5, 5E, OR HIGHER
3. Do not run in same conduit, raceway, or chase as high voltage wiring.
4. For CANbus network lengths greater than 450FT (137M) call Factory.
DPN002169
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LIEBERT MC CONDENSER
ELECTRICAL FIELD CONNECTIONS
PREMIUM EFFICIENCY CONTROL
REV : 10
REV DATE : 2/17