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Bryant DURAPACK 558F User Manual

Page 25

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25

D. EconoMi$er IV Standard Sensors

Outdoor Air Temperature (OAT) Sensor

The outdoor air temperature sensor (HH57AC074) is a 10 to
20 mA device used to measure the outdoor-air temperature.
The outdoor-air temperature is used to determine when the
EconoMi$er IV can be used for free cooling. The sensor is
factory-installed on the EconoMi$er IV in the outdoor
airstream. See Fig. 17. The operating range of temperature
measurement is 40 to 100 F.

Supply Air Temperature (SAT) Sensor

The supply air temperature sensor is a 3 K thermistor
located at the inlet of the indoor fan. See Fig. 27. This sensor
is factory installed. The operating range of temperature mea-
surement is 0° to 158 F. See Table 3 for sensor temperature/
resistance values.

FOR OCCUPANCY CONTROL
REPLACE JUMPER WITH
FIELD-SUPPLIED TIME CLOCK

LEGEND

DCV — Demand Controlled Ventilation
IAQ — Indoor Air Quality
LA

Low Ambient Lockout Device

OAT — Outdoor-Air Temperature
POT — Potentiometer
RAT — Return-Air Temperature

Potentiometer Defaults Settings:
Power Exhaust

Middle

Minimum Pos.

Fully Closed

DCV Max.

Middle

DCV Set

Middle

Enthalpy

C Setting

NOTES:

1. 620 ohm, 1 watt 5% resistor should be removed only when using differential

enthalpy or dry bulb.

2. If a separate field-supplied 24 v transformer is used for the IAQ sensor power

supply, it cannot have the secondary of the transformer grounded.

3. For field-installed remote minimum position POT, remove black wire jumper

between P and P1 and set control minimum position POT to the minimum
position.

Fig. 23 — EconoMi$er IV Wiring

0

500

1000

1500

2000

2500

0.05

0.15

0.25

STATIC PRESSURE (in. wg)

FLOW IN CUBIC FEET

PER MINUTE (cfm)

0

5

10

15

20

25

30

0.13 0.20 0.22 0.25 0.30 0.35 0.40 0.45 0.50

STATIC PRESSURE (in. wg)

FLOW IN CUBIC FEET

PER MINUTE (cfm)

Fig. 24 — Barometric Flow Capacity

Fig. 25 — Outdoor-Air Damper Leakage

0

1000

2000

3000

4000

5000

6000

0.05 0.10 0.15 0.20 0.25 0.30 0.35

STATIC PRESSURE (in. wg)

FLOW IN CUBIC FEET

PER MINUTE (cfm)

Fig. 26 — Return-Air Pressure Drop