Normal Control
SiME341909EA
62
Part 4 Functions and Control
5.3 Compressor Capacity Control
Te: Low pressure equivalent saturation temperature
Capacity steps
The compressor rotation speed is changed according to the control pressure.
Cooling: suction pressure sensor value is converted into evaporation saturated temperature
(relation between pressure and evaporating temperature based on characteristics of
refrigerant R-410A). For detailed explanation refer to chapter field settings (
Details of
Setting Mode (Mode 2)
on page 119 and installation manual outdoor chapter Energy saving
and optimum operation).
Initial selection is made between Automatic, Fixed or High sensible.
During operation, the outdoor target evaporating temperature can be changed based on
the selected sub function, taking indoor load into account.
The initial target saturated temperature can be changed. For details refer to
Details of
Setting Mode (Mode 2)
on page 119 for Cooling: Te set based on field setting 2-8.
During operation, outdoor control will take into account the pressure drop so that at indoor
units, the preset target temperature is reached (average). The estimated pressure drop is
calculated based on:
Pressure drop characteristics found during test-operation outdoor (step 7). At several
evaporating temperatures, outdoor control stores difference between outdoor
evaporating temperature and average of indoor heat exchanger (indoor evaporating
temperature).
To have judgment of gas speed in main suction pipe, control takes the capacity step of
the outdoor unit into account. In function of pressure drop characteristics at the different
compressor capacity steps, control concludes the category of system pipe lay out (long,
medium, short).
Target Te outdoor (cooling) = Te set – estimated pressure drop –
A
.
Correction factor
A
depends on the absolute value of the difference between indoor air inlet
temperature and a set temperature after startup period.
Summary of Contents for VRV X RXQ10ARYFK
Page 1: ...Service Manual Cooling Only 50 60 Hz RXQ6 48A N R Series SiME341909EA...
Page 289: ...SiME341909EA Wiring Diagrams Part 7 Appendix 283 RXQ10 12ARYFK 2D124184...
Page 290: ...Wiring Diagrams SiME341909EA 284 Part 7 Appendix RXQ14 16ARYFK 2D124183...
Page 295: ...SiME341909EA Wiring Diagrams Part 7 Appendix 289 FXMQ40 50 63 80 100ARV1 3D127112 04 59...
