REV : 3
REV DATE : 1/20
DPN004797
Page :1 /3
DA250, DA265 DOWNFLOW MODELS
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ELECTRICAL FIELD CONNECTIONS
LIEBERT
®
DSE
STANDARD ELECTRICAL CONNECTIONS
1)
High voltage entrance - Located in bottom and top of box (quantity 3)
2)
Low voltage entrance – Located in bottom and top of box (quantity 4)
3)
Three phase electrical service - Terminals are on top of disconnect switch. Three phase service not
provided by Liebert.
4)
Earth ground - Terminal for field supplied earth grounding wire and component ground terminal strip.
Earth grounding required for Liebert units.
5)
Unit factory installed disconnect switch and Main Fuses – Access to the high voltage electric panel
compartment can be obtained only with the switch in the “off” position. Fused disconnects are provided
with a defeater button that allows access to the electrical panel when power is on.
6)
Remote unit shutdown - Replace existing jumper between terminals 37 & 38 with field supplied normally
closed switch having a minimum 75VA, 24VAC rating. Use field supplied Class 1 wiring.
7)
Customer alarm inputs - Terminals for field supplied, normally open contacts, having a minimum 75VA,
24VAC rating, between terminals 24 & 50, 51, 55, 56. Use field supplied Class 1 wiring. Terminal
availability varies by unit options.
8)
Common alarm - On any alarm, normally open dry contact is closed across terminals 75 & 76 for remote
indication. 1 AMP, 24VAC max load. Use Class 1 field supplied wiring.
9)
Heat rejection interlock - On any call for compressor operation, normally open dry contact is closed
across terminals 70 & 71 & 230 to heat rejection equipment. 1 AMP, 24VAC max load. Use Class 1 field
supplied wiring.
CANbus ELECTRICAL CONNECTIONS
10)
CANbus Connector – Terminal block with terminals 49-1 (CAN-H) and 49-3 (CAN-L) + SH (shield
connection). The terminals are used to connect the CANBus communication cable (provided by others)
from the indoor unit to the Liebert MCV Condenser skid
11)
CANbus Cable – CANbus cable provided by others to connect to the outdoor condenser and optional
PRE unit. No special considerations are required when the total external cable connection between the
indoor unit and outdoor unit(s) is less than 450FT (137M). For total external cable connections greater
than 450FT (137M). For external cable connections greater than 450FT (137M), but less than 800FT
(243M) a CANbus isolator is required (Contact Factory).
Cable must have the following specifications:
- 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
- Do not run in same conduit, raceway, or chase as high voltage wiring.
- For CANbus network lengths greater than 450FT (137M) call Factory.
