Sinclair SCV-750EB Service Manual page 35

Electronic expansion valve
Electronic expansion valve
Four-way valve
Solenoid valve (defrost)
Solenoid valve (by pass)
Solenoid valve (injection)
Water side heat exchanger
heater
Water flow switch
Water flow switch heater
Crank case heater
For SCV-1800EB:
Component
Inverter compressor
DC fan motor
Electronic expansion valve
Four-way valve
5.3 Compressor Output Control
The compressor rotation speed is controlled according to the load requirement. Before compressor startup, the outdoor unit
determines the compressor target speed according to outdoor ambient temperature, discharge temperature and then runs the
appropriate compressor startup program. Once the startup program is complete, the compressor runs at the target rotation
speed.
The compressor speed is controlled according to two parts in normal operation:
In cooling mode: In a single system, the compressor speed is controlled according to the water outlet temperature and water
outlet setting temperature. In a combination system, the compressor of master unit is controlled according total water outlet
temperature and water outlet setting temperature, the compressor of the slave unit is controlled according to water inlet and
water outlet temperature. Both in a single system and combination system, the compressor speed is limited by the inverter
module temperature (calculated value), ambient temperature, discharge temperature, discharge pressure and air side heat
exchanger refrigerant total outlet temperature.
EXV-B
EXV-C
ST1
SV5
SV6
SV8A/B
-
Water-SW
-
CCH
Wiring diagram label
180kW
BP1/2
FAN
EXV
ST1
Step from 0 to 480. Controlled according to discharge
● ●
temperature superheat.
Enhanced vapor injection EXV, Step from 0 to 480.
Controlled according to temperature difference
● ●
between economizer plate heat exchanger inlet and
outlet.
● ●
Closed
● ●
Closed
● ●
Closed
● ●
Open
According to water side heat exchanger anti-freezing
● ●
temperature
After water pump (field supplied) is turned on for
2min, if water flow switch is open, water pump stops
● ●
and water flow error code appears. The compressor
can be started after the water flow is normal.
Controlled according to ambient temperature, water
● ●
inlet temperature and water outlet temperature
Controlled according to ambient temperature and
● ●
discharge temperature
Controlled according to load requirement from hydronic system.
●
Controlled according to outdoor heat exchanger pipe temperature.
●
Position (steps) from 0 (fully closed) to 480 (fully open), controlled
according to
●
temperature, suction superheat, compressor speed and refrigerant
system pressure.
Off
●
Control functions and states
outdoor ambient temperature, discharge
33