Mitsubishi Heavy Industries SRK20ZJX-S Service Manual page 27

2) Remote operation input
Remote operation input connector (CnT-6) is provided on the indoor control PCB.
However remote operation by CnT-6 is not effective, when "Center mode" is selected by center controller.
In case of plural unit (twin, triple, double twin), remote operation input to CnT-6 on the slave indoor unit is invalid.
Only the "LEVEL INPUT" is acceptable for external input, however when the indoor function setting of "Level
input (Factory default)" or "Pulse input" is selected by the function for "External input" of the wired remote controller,
operation status will be changed as follows.
a) In case of "Level input" setting (Factory default)
Input signal to CnT-6 is OFF→ON ...... unit ON
Input signal to CnT-6 is ON→OFF ...... unit OFF
Operation is not inverted.
CnT-6 input
Note: The latest operation has priority
It is available to operate/stop by remote controller or center controller
b) In case of "Pulse input" setting (Local setting)
It is effective only when the input signal to CnT-6 is changed OFF→ON, and at that time unit operation [ON/OFF] is
inverted.
CnT-6 input
Unit A
Unit B
3) Remote operation
a) In case of multiple units (Max. 16 indoor units group) are connected to one wired remote
controller
When the indoor function setting of wired remote controller for "External control set" is changed from "Individual
(Factory default)" to " For all units", all units connected in one wired remote controller system can be controlled by
external operation input.
Outdoor unit Outdoor unit Outdoor unit Outdoor unit
123
Signal &
Power
External
input
123
XY
Indoor unit
Indoor unit
XY
Wired remote controller
ON
OFF
ON
Unit A
OFF
ON
Unit B
ON
OFF OFF
ON
OFF
ON
OFF
123 123 123
123 123 123
XY XY XY
Indoor unit
Indoor unit
(master)
Ex. Indoor units =
-
ON
OFF OFF
ON
OFF
OFF
ON
OFF
OFF
ON
OFF
OFF
ON
Outdoor unit
123
123
XY
Indoor unit
26
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'10 • SCM-SM-094