Determination Of Initial Frequency - Daikin FTX25JVEA9 Service Manual

Si18-201
3.6

Determination of Initial Frequency

3.6.1 Determination of Operation Frequency
Purpose of the To control the operating frequency in order to ensure compressor reliability and optimise the
operating condition.
Function
∆
Outline
used to determine the frequency corresponding to the capacities of the indoor units connected
to the BP units.
This function is also described in the following section.
Method of determining frequency
Method of determining frequency
The compressor operating frequency is determined in the following steps.
1. Selection of command frequency FSR
2. Selection of upper-limit frequency FMAX
3. Selection of lower-limit frequency FMIN
4. Selection of restriction frequency FSG
5. Execution of prohibit frequency skip control
6. Selection of target frequency FMK
Main Functions
D signals (difference between room temperature and temperature setting) from BP units are
When FSR ≥ droop buffer: copy
FSR
Initial frequency
PI control
MIMO control
Defrost
Frequency fixed mode, etc.
Individual droop function
buffer
Peak-cut control, etc.
Individual upper-limit buffers
FMAX
Compressor protection
function, etc.
Skip control
FSG
FMIN
Individual lower-limit buffers
4-way valve operation security
Wet protection function, etc.
System control
FMK
(M1008)
115