Compressor Protection Function - Daikin FTK25JVE9 Service Manual

General Functionality
1.17

Compressor Protection Function

Outline An refrigeration oil level descent and progression of the dilution which will arise at operation of
the compressors will be avoided by controlling the upper limit of frequency at the edge of
compressor's changeover from OFF to ON as follows.
Processing
1. A choice of a constant based on the starting conditions.
A constant is chosen in the following conditions at the start of compressors.
∗
∗
∗
2. Frequency control
The following control is carried out after the judge of 1. above. A constant is chosen in
accordance with A, B decided in 1).
3. Others
∗
∗
38
Compressor operation frequency
F CG3
F CG2
F CG1
T CG0
Power ON
In case TCG0 < TDEN
A type starting is adopted.
In case TCG0 ≥ TDEN
B type starting is adopted.
TCG0 is set only at power-ON and then start, keep counting regardless of the operation mode.
The judge above should be done only at the start of compressors.
TCG : Timer guard for compressor protection
Timer TCG1 (A,B) will start at the start of compressors.
The upper limit of output frequency in between TCG1 (A,B) is set at FCG1 (A,B).
In exceeding TCG1 (A,B), timer TCG2 (A,B) starts and the upper limit of output frequency in
between TCG2 (A,B) is set at FCG2(A,B).
In exceeding TCG2 (A,B), timer TCG3 (A,B) starts and the upper limit of output frequency in
between TCG3 (A,B) is set at FCG3(A,B).
In exceeding TCG3 (A,B), the frequency limit is cancelled.
If compressors go off at the start of this function, the timer under counting should be reset
and cancelled the frequency limit.
This function doesn't work under the control of defrosting.
Setting a constant
FCG1A
FCG1B
FCG2A
FCG2B
FCG3A
FCG3B
FCG : Frequency guard for compressor protection
TCG : Timer guard for compressor protection
T CG1 T CG2
∗
TDEN : Elapsed time after power-on
J type Setting a constant
46 Hz TCG1A
46 Hz TCG1B
66 Hz TCG2A
66 Hz TCG2B
90 Hz TCG3A
80 Hz TCG3B
TDEN
time
T CG3
(R1907)
J type
120 sec
120 sec
570 sec
360 sec
120 sec
180 sec
30 min
Main Function
Si04-115