Liebert ITR 2.7 Balancing the Air Distribution

Installation

9. Special alarm connections. Field-supplied 24V Class 1 wiring for special alarm. Connection

made by adding normally open contacts between terminals 24 + 50. Optional additional

connections available with Advanced or Advanced with Graphics controls and appropriate

optional accessories (connections 51, 55, and 56).

10. Liebert SiteScan® connection. Terminals 77 (-) and 78 (+) are for connection of a 2-wire, twisted

pair, communication cable (available from Liebert or others) to optional Liebert SiteScan.

11. Remote condensing unit connection. Field-supplied 24V Class 1 wiring to remote condensing

unit terminals 1, 2, 3, & 4 from (R2) relay (split system only).

12. Smoke detector alarm connections. Field-supplied 24V Class 1 wiring to remote alarm circuits.

Factory-wired contacts from optional smoke detector are #91-comm., #92-NO, and #93-NC.

13. Common alarm connection. Field-supplied 24V Class 1 wiring to common alarm terminals 75 + 76

(and optional 94 + 95, and 96 + 97), which are factory-connected to common alarm relay (R3).

14. Reheat and Humidifier Lockout. Optional emergency power lockout of reheat and/or humidifier:

connections provided for remote 24V AC source.

15. Heat rejection connection. Field-supplied 24V Class 1 wiring to interlock heat rejection from

pigtails 70 + 71 which are factory-connected to compressor side switch (self-contained units only

and to Glycool relay (R5), Glycool units only).

16. Main Fan Auxiliary Switch. Optional main fan auxiliary side switch. Terminals located in field

wiring compartment for remote indication that the evaporator fan motor/unit is on. Field to

connect 24V maximum.

17. Optional Condensate Alarm (Dual Float Condensate Pum p only). Relay terminals located in field

wiring compartment for remote indication.

*Located inside Liebert Challenger ITR on top.

NOTE: Refer to specification sheet for full load amp. and wire size amp. ratings.

2.7 Balancing the Air Distribution

For ducted applications, the duct work may be attached to the top perimeter of the Liebert Challenger

ITR (see Figure 2).

The duct work must allow access to the motors/blowers for maintenance. The duct work must be

designed within the capacity of the Liebert Challenger ITR, otherwise air flow and performance will

be compromised.

A solid plenum or plenum with discharge grille(s) may be installed. The plenum and instructions for

its installation ship separately from the Liebert Challenger ITR.