![Fig. 19 Ð Field Control Thermostat Wiring](/images/new-backgrounds/33676/3367667x1.webp)
CONTROL WIRING Ð Install a
Total wire lengths should not exceed the following limits: 50 ft of 18 AWG, 80 ft of 16 AWG or 125 ft of 14 AWG. See Fig. 19 for ®eld wiring connections between the thermostat and the unit
There are no required
Options requiring
Building Pressurization or Smoke Purge Mode Ð Refer to appropriate unit Controls and Troubleshooting literature as necessary for additional information. See Fig. 20 and unit wiring label for wiring details.
1.Firestat or smoke detector
2.Switch to drive economizer
3.Switch to disconnect power to economizer motors (®eld- supplied
4.Building pressurization switch
Fig. 19 Ð Field Control Thermostat Wiring
TB2 and the C1 connection on the
5.Switch to isolate
Modulating Power Exhaust Ð Wire a
Constant Volume Power Exhaust Ð Wire a
6.Switch to energize power exhaust motor
7.Switch to fully open power exhaust damper (®eld- supplied
NOTES AND LEGEND FOR FIG. 20
BUILDING PRESSURIZATION | SMOKE PURGE | ALARM |
Switch 1 | Switch 1 | Switch 1 |
Switch 2 | Switch 2 | Switch 3 |
Switch 4 | Switch 5 |
|
Switch 5 | Switch 6 |
|
| Switch 7 (MPE) |
|
Switch 1 | Ð Remove jumper. Firestat or smoke detector Ð | |
Switch 2 | Ð | normally closed. |
Switch to drive economizer | ||
Switch 3 | Ð | open Ð normally open. |
Switch to disconnect power to economizer motors. | ||
|
| Drives economizer |
Switch 4 | Ð | normally closed. |
Building pressurization switch (energize evaporator- | ||
Switch 5 | Ð | fan motor) Ð normally open. |
Switch to isolate | ||
Switch 6 | Ð | closed. |
Switch to energize power exhaust motors Ð normally | ||
|
| open. |
Switch 7 | Ð Switch to fully open power exhaust damper Ð | |
|
| normally open. |
LEGEND
CÐ Contactor
DPS | Ð Differential Pressure Switch |
DMS | Ð Damper Motor Switch |
ECON Ð Economizer | |
IFC | Ð Indoor (Evaporator) Fan Contactor |
MPE | Ð Modulating Power Exhaust |
NC | Ð Normally Closed |
NO | Ð Normally Open |
PEC | Ð Power Exhaust Contactor Coil |
PL | Ð Plug |
SW | Ð Switch |
TB | Ð Terminal Block |
TRAN | Ð Transformer |
NOTES:
1.Power exhaust option can be unit mounted on vertical supply/ return units only.
2. is ®eld wiring.
3.is ®eld wiring.
4.Switches
5.For building pressurization, ®eld supplied power source must drive room terminals wide open.
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