Main Functions; Frequency Principle - Daikin FTKS20D3VMW Service Manual

Main Functions

1. Main Functions

Note: See the list of functions for the functions applicable to different models.
1.1

Frequency Principle

Main Control The compressor is frequency-controlled during normal operation. The target frequency is set by
the following 2 parameters coming from the operating indoor unit:
Parameters
" The load condition of the operating indoor unit
" The difference between the room temperature and the set temperature
Additional The target frequency is adapted by additional parameters in the following cases:
" Frequency restrictions
Control
" Initial settings
Parameters
" Forced cooling / heating operation
Inverter Principle
To regulate the capacity, a frequency control is needed. The inverter makes it possible to vary
the rotation speed of the compressor. The following table explains the conversion principle:
Drawing of The following drawing shows a schematic view of the inverter principle:
Inverter
60
Phase
1 The supplied AC power source is converted into the DC power source for the present.
2 The DC power source is reconverted into the three phase AC power source with variable
frequency.
" When the frequency increases, the rotation speed of the compressor increases resulting
in an increased refrigerant circulation. This leads to a higher amount of the heat
exchange per unit.
" When the frequency decreases, the rotation speed of the compressor decreases
resulting in a decreased refrigerant circulation. This leads to a lower amount of the heat
exchange per unit.
Amount of heat
exchanged air (large)
Amount of heat
exchanged air (small)
freq=
constant
Description
Refrigerant circulation rate (high)
high speed
high f
low f
low speed
50 Hz 50 Hz
capacity=
60 Hz 60 Hz freq=variable
variable
Refrigerant circulation rate (low)
SiENBE12-713
Amount of heat
exchanged air (large)
Amount of heat
exchanged air (small)
(R2812)
Function and Control