Compressor Pi Control - Daikin RXYQ96PYDN Service Manual

SiUS34-801A_b
*1 and 2 : Refer to Chapter 6: Control of Electonic Expansion Valve on page 293.
BS unit actuator
Electronic expansion valve (EVH)
Electronic expansion valve (EVL)
Electronic expansion valve (EVHS)
Electronic expansion valve (EVLS)
Electronic expansion valve (EVSC)
6.2

Compressor PI Control

Compressor PI Control
Carries out the compressor capacity PI control to maintain Te at constant during cooling operation
and Tc at constant during heating operation to ensure stable unit performance.
[Cooling operation]
Controls compressor capacity to adjust Te to
achieve target value (TeS).
Te set value (Make this setting while in Setting
mode 2.)
Te setting
[Heating operation]
Controls compressor capacity to adjust Tc to
achieve target value (TcS).
Te set value (Make this setting while in Setting
mode 2.)
Tc setting
Rotation of outdoor units
In order to make operating time equal for each compressor of multi connection outdoor units,
outdoor units are used in rotation.
However this is not applicable to single units.
[Rotation of outdoor units]
For multiple outdoor units, an operational priority order is assigned to each outdoor unit on the
control purpose.
The operational priority orders of each outdoor unit are switched by means of outdoor unit rotation.
[System with two outdoor units]
[Timing of outdoor rotation]
In start of startup control
VRVIII R-410A Heat Recovery 60Hz
Electric
Normal cooling
symbol
Y4E 760 pls (fully opened)
Y5E 760 pls (fully opened)
Y2E 480 pls (fully opened)
Y3E 480 pls (fully opened)
Y1E
L M (Normal)
(factory
setting)
37 43 45 46 48 50 52
L M (Normal) H
(factory
setting)
109 115 118
Outdoor Unit 1
Previous time
This time
Next time
Normal heating / Normal simultaneous Cooling /
0 pls 0 pls (simultaneous Cooling / Heating operation : PI control)
Te : Low pressure equivalent saturation temperature
(°F)
TeS : Target Te value
(Varies depending on Te setting, operating
frequency, etc.)
H
*On multi-outdoor-unit systems, this control is made
according to values of the first-priority unit, which is
detected with the pressure sensor.
Tc : High pressure equivalent saturation temperature
(°F)
TcS : Target Tc value
(Varies depending on Tc setting, operating
frequency, etc.)
*On multi-outdoor-unit systems, this control is made
according to values of the first-priority unit, which is
detected with the pressure sensor.
Outdoor Unit 2
Priority 1
Priority 2
Priority 1
Heating operation
760 pls (fully opened)
0 pls
480 pls (fully opened)
0 pls
Priority 2
Priority 1
Priority 2
Basic Control
189