Mitsubishi Heavy Industries FDT28KXE6A Service Manual page 21

CM01
(M=0)
Master unit
(N=0)
CM02
(M=1)
CM11
(M=0)
Slave unit
(N=1)
CM12
(M=1)
⑥ When master unit retains the current safe control information in itself or receive the current safe control informa-
tion from slave unit, master unit send signal of "Current safe protective control" to the indoor units during retain-
ing those information.
At-end condition: If either following condition ① or ② is established, the protective control 3) will end and return to
4)
the PI control.
① The detected inverter current is -1A or lower of the current safe value for 3 minutes continuously.
② The detected inverter current is lower than the current safe value for 6 minutes continuously
< Maximum compressor frequency control>
1) By controlling the maximum compressor frequency according to the rising outdoor air temperature, it makes the in-
verter secondary current decreasing and protects the controller from rising temperature.
Compressor frequency is also controlled by detecting inverter secondary frequency
Initiation condition: Outdoor air temperature > = 35ºC ( For cooling operation)
2)
3) Control contents
① Maximum compressor frequency is varied according to following chart.
Whichever the lower of maximum compressor frequency by this control or at normal operation has priority.
120
100
80
60
40
* Maximum compressor frequency can be corrected by the code P21 of 7-segment input.
Correction value β = 4 × α
( α : Correction coefficient of current safe value)
4) At-end condition: Initiation conditions are not established.
OFF
OFF
OFF
OFF
120 120
113 113
96 96
37 39 43
Outdoor air temperature (°C)
1
- -
ON
ON
Current safe
control
ON
Retain
ON
76 76
50 50
47 50
PI control
Release