Component Control During Startup In Cooling Only/Main Cooling Mode - Midea VRF Series Service Manual

4.3 Startup Control for Cooling Only/Main Cooling Operation
Table 3-4.1: Component control during startup in cooling only/main cooling mode
Component
Inverter
compressor A
Inverter fan 1
Inverter fan 2
Four way valve
ODU
Electronic
expansion valve
Solenoid valve
Electric ball
valve
MS01
Electronic
expansion valve
Solenoid valve
MS04-12
Electronic
expansion valve
Fan
IDU
Electronic
expansion valve
Ending conditions
Notes:
1. The period for restarting after stopping is 7min when is necessary to equalize the pressure in the whole system.
Wiring
1
Before startup
diagram
label
INV1 0Hz
FANA
0 Step
FANB
Maintains previous
ST1
position
EEVA 0pls
EEVC 0pls
SV5 OFF
SV8A OFF
SV7 OFF→ON for 1min
OFF
EVBA
EVBB OFF
EVBC OFF
EEVA 240 pulse
OFF
SV(n)A
OFF
SV(n)B
OFF
SVP
EEVA 240pls
Fan 0 step
300pls (500P EEV)
EEV 1200pls (2000P
EEV)
60S
STEP1
Initial step for 30S, then+8Hz×Nstep /
0Hz 10S. (Until it reaches Pc_max-Pe_min ≥
0.2MPa)
Start: 0 step, then adjust by the high
0 step
pressure and low pressure
Determined based on the initial mode of the heat exchanger
Compressor operation, 2880pls
Compressor not operation, initial 135pls, then adjusted according to the
module temperature NTC.
Compressor operation, 17pls→ +8pls per 20S based on high
0pls pressure or discharge temperature.
Compressor not operation, 0pls.
ON
Compressor operation, ON
OFF
Compressor not operation, OFF
ON if Pc≥3.3MPa or Pe ＜ 0.18MPa, else OFF.
ON
Control based on IDUs' mode
2950pls
0pls
Control based on IDUs' mode
OFF
0pls
Setting speed by owners
500P EEV IDU: Maintain 300pls for 5min
2000P EEV IDU : Maintain 1200pls for 5min
End if startup time arrives 5 min or the minimum superheat of discharge
temperature ≥10°C or Tc_max > 50°C.
V6R VRF 50/60Hz
Startup control
STEP2
8-10HP 42Hz, 12-
22HP 51Hz, 24-34HP
88HZ, 36-60HP
138Hz,
then adjust according
to the high pressure
and low pressure etc.
PI control
STEP3
29