11-1
CONTROL SYSTEM
SM BS DCI 1- A.1 GB
11. CONTROL
SYSTEM
11.1
General Functions and Rules (for single split models)
The DCI software is fully parametric.
All the model dependent parameters are shown in Blue color and with Italic sty
[
parameter
].
The parameters values are given in the last section of this control logic chapte
service manual.
11.2
System Operation Concept
The control function is divided between indoor and outdoor unit controll
Indoor unit is the system ‘Master’, requesting the outdoor unit for cooling/hea
capacity supply. The outdoor unit is the system ‘Slave’ and it must supply
required capacity unless it enters into a protection mode avoiding it f
supplying the requested capacity.
The capacity request is transferred via indoor to outdoor communication, an
represented by a parameter called ‘NLOAD’. NLOAD is an integer number w
values between 0 and 127, and it represents the heat or cool load felt by
indoor unit.
11.3
Compressor Frequency Control
11.3.1
NLOAD setting
The NLOAD setting is done by the indoor unit controller, based on a PI contro
scheme.
The actual NLOAD to be sent to the outdoor unit controller is based on the
preliminary LOAD calculation, the indoor fan speed, and the power shedding
function.
NLOAD limits as a function of indoor fan speed:
Indoor Fan Speed Maximum NLOAD Cooling
Maximum NLOAD Heating
Low
Max NLOADIF1C
127
Medium
Max NLOADIF2C
127
High
Max NLOADIF3C
127
Turbo
Max NLOADIF4C
127
Auto
Max NLOADIF5C
127
NLOAD limits as a function of power shedding:
CONTENTS
