Carrier 50TC-D25 - EconoMi$er IV Control Modes

42
C06053
Fig. 48 − EconoMi$er IV Functional View
EconoMi$er IV Standard Sensors
Table 9 provides a summary of EconoMi$er IV I/O logic.
A functional view of the EconoMi$er is shown in Fig. 48.
Typical settings, sensor ranges, and jumper positions are
also shown. An EconoMi$er IV simulator program is
available to help with EconoMi$er IV training and
troubleshooting.
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. 49. The
operating range of temperature measurement is 40 to
100F (4 to 38C). See Fig. 67.
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. 49. This
sensor is factory installed. The operating range of
temperature measurement is 0° to 158 F (−18 to 70C).
See Table 49 for sensor temperature/resistance values.
The temperature sensor looks like an eyelet terminal with
wires running to it. The sensor is located in the “crimp
end” and is sealed from moisture.
Outdoor Air Lockout Sensor
The EconoMi$er IV is equipped with an ambient
temperature lockout switch located in the outdoor
airstream which is used to lock out the compressors below
a 42F (6C) ambient temperature. See Fig. 61.
SUPPLY AIR
TEMPERATURE
SENSOR
(SEALED
INSIDE CRIMP
END)
SUPPLY
AIR TEMPERATURE
SENSOR MOUNTING
LOCATION
C06033
Fig. 49 − Supply Air Sensor Location
EconoMi$er IV Control Modes
IMPORTANT: The optional EconoMi$er2 does not include
a controller. The EconoMi$er2 is operated by a 4 to 20
mA signal from an existing field-supplied controller. See
Fig. 62 for wiring information.
Determine the EconoMi$er IV control mode before set up
of the control. Some modes of operation may require
different sensors. The EconoMi$er IV is supplied from the
factory with a supply−air temperature sensor and an
outdoor− air temperature sensor. This allows for operation
of the EconoMi$er IV with outdoor air dry bulb
changeover control. Additional accessories can be added
to allow for different types of changeover control and
operation of the EconoMi$er IV and unit.