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7.0 COMPONENTS & CONTROLS
7.2 Power Inverter
Compressor Control
(-)A15AZ/(-)P16AZ/(-)A16AZ outdoor units are
equipped with a power inverter that varies the
compressor speed to match the changing capac-
ity needs of the conditioned space. The inverter
interfaces with the Variable Speed Outdoor Control
(VSODC) which communicates the level of system
capacity that is required to the inverter based on
input from the EcoNet
TM
Control Center or con-
ventional 24VAC 2-stage thermostat. The inverter
converts incoming single phase power to simulated
variable frequency 3-phase power that is connect-
ed to the 3-phase compressor motor. Each of the
four (-)P20 models has a unique inverter specifical-
ly designed and qualified for that specific model to
provide reliable operation under the most extreme
conditions. Each inverter is programmed to moni-
tor compressor power consumption, motor torque,
input current, input voltage, compressor discharge
pressure, and compressor discharge temperature.
When the inverter identifies a condition that could
potentially result in compressor or inverter damage,
it automatically reduces the compressor speed
until a more reliable operating condition is obtained
or shuts the compressor completely off if neces-
sary. Once safe operating conditions are attained,
the inverter will gradually increase the compressor
speed in an attempt to meet the capacity demand
as long as the operating conditions remain within
the safe operating range of the compressor and
inverter.
1. RS485 Communication
2. Input Power
3. Drive Output
4. OD Fan Motor
Components
1
2
3
4
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