Electrical Connections - Trane GRAA Installation Operation & Maintenance

ELECTRICAL CONNECTIONS
All electrical
connections must
conform to:
ANSI/NFPA No. 70-1993 (or latest edition) National
Electrical Code and applicable local codes. In
Canada, to the Canadian Electrical Code, Part I CSA
Standard C22.1.
The rooftop packaged unit is wired at the factory and
ready to be connected. Actual unit wiring will differ
according to the options chosen. Each furnace is
shipped with its own wiring diagram; refer to this
wiring diagram for all electrical connections to the
unit.
All electrical connections, line voltage and thermo-
stat, are made in the Electrical Cabinet (See Figure
6). Line voltage connections are made at the High
Voltage Terminal Block. Thermostat connections are
made at the Main Connection Board (See figure 7).
CAUTION : Do not use any tools (i .e . screwdriver,
pliers , etc . ) across terminals to check for power.
Use of a voltmeter is recommended .
Outdoor line voltage conduits leading into the unit
should be installed to prevent rain from wetting any
high voltage wire. Locate the thermostat in accor-
dance the instructions supplied with the thermostat.
All field wiring must have a minimum temperature
rating of 85° C (185° F). Thermostat wiring shall be a
minimum of 18 gauge wire size. See the following
charts for line voltage wire sizes.
Figure 6 . - Standard Blower Cabinet , Single Duct Furnace with Supply Plenum & Various Options Shown
1 . Mixed Air Controll e r
2 . Return Firestat
3 . Econom izer
4. Filters
5. Bl ower M otor
6. Reverse Air Flow Sw itch
7. Clog ged F ilter Switch
8. Hi gh Voltage B arrier and Lamp
and C i rcuit Breaker Mount
9 . Main Connect i on Board with Fan
Time Delay and Function Relays
10 . Powe r Ve ntor Relay
11 . Freezestat
12 . Supply Fires tat
13. Duct The rm ostat
14. Primary Safety Limit
15. Power Ventor Motor
16. Gas Piping Limit
17. Gas Valve
18. High Limit Safety Switch
19. Transformer
20. Electrical Wiring Inlet
21. High Voltage Terminal Block
22. Door Safety Switch
23. Contactor
24. Centrifugal Blower
25. Damper Motor
26. Outside and Return Dampers
27. Enthalpy Controlled Economizer
-9-
Intake Hood
Dampers/Filters
Electrical Duc t
Supp l y
Blower Cabinet
Cabinet F urnace
Plenum