Mitsubishi Electric AT-50A Installation Manual page 7

1-7. Using external input/output
1. External signal input (CN2)
*To use external input, an external input/output adapter (PAC-YT41HAA; sold separately) is required.
(1) External input
Using external dry contact signals, the following operation of all air conditioning units can be controlled from the AT-50A: Emergency stop/Normal
operation, ON/OFF, Permit/Prohibit local remote controller operation. These settings are made on the External Input Settings on the Initial Settings
screen that is accessible from the Service Menu screen. (Refer to section 2-3.)
Mode
1 Do not use external input. (Factory setting)
Emergency stop/Normal operation signal (level
2
signal)
3 ON/OFF signal (level signal)
ON/OFF and Prohibit/Permit remote controller
4
operation signal (pulse signal)
(2) Level signal and pulse signal
(A) Level signal
Contact ON
Contact OFF
OFF
Contact ON
Contact OFF
Normal
operation
(3) External input specifications
CN2 Lead wire
1 Green
2 Yellow
3 Orange
4 Red
5 Brown
(A) Level signal
• If the type of signal assigned to the external input contact is "Emergency/Normal," the units in normal operation will stop when the signal
input changes from OFF to ON. Conversely, the units that are stopped will resume normal operation when the signal changes from ON to
OFF. After the emergency stop is reset, the original operating status of each air conditioning unit will not be automatically restored. The air
conditioning units must be started up manually.
• If the type of signal assigned to the external input contact is "ON/OFF," the units that are stopped will start operation after the input signal
changes from OFF to ON. Conversely, the units that are in operation will stop after the input signal changes from ON to OFF.
(B) Pulse signal
• If the incoming signal is the same as the signal that is currently being received, no status change will occur.
• If local remote controller operation is prohibited, ON/OFF status, operation mode, or temperature setting cannot be changed and filter sign
cannot be reset from the remote controller.
• The ON-signal pulse width should be set to a value between 0.2 and 1 seconds.
(4) Sample circuit recommended
(A) Level signal
External input signal setting
ON
OFF
Emergency Normal
operation
stop
Emergency stop/Normal
operation signal (level signal)
Built-in 5 VDC power for external input * Exclusively for use with external input. Not usable for other purposes.
Emergency stop/Normal operation
signal input
Not used
Not used
Not used
CN2
Green
1
X1
Yellow
2
3
or Emergency stop
4
5
Maximum
10 m
(32 ft) Field supplied
AT-50A
When the units are not operating after receiving an emergency stop signal, the ON/
OFF operation from the local remote controller will not be allowed, and the ON/OFF
and Prohibit/Permit settings on the AT-50A cannot be changed. Timer operation will
not function.
ON/OFF operation from the local remote controller will not be allowed, and the ON/
OFF and Prohibit/Permit settings on the AT-50A cannot be changed. Timer
operation will not function.
The ON-signal pulse width should be set to a value between 0.2 and 1 seconds.
(B) Pulse signal
(ex.)ON/OFF
Contact ON
Signal 1 (ON)
Contact OFF
Contact ON
Signal 2 (OFF)
Contact OFF
*Same for Prohibit/Permit remote controller operation.
ON/OFF level signal
ON/OFF signal input
Not used
Not used
Not used
(B) Pulse signal
X1
ON/OFF
– 7 –
Notes
–
0.2 to 1 seconds
0.2 to 1 seconds
ON OFF
OFF
ON/OFF, Prohibit/Permit remote
controller operation (pulse signal)
ON signal input
OFF signal input
Prohibit-local-remote-controller-
operation signal input
Permit-local-remote-controller-
operation signal input
CN2
Green
1
Yellow X1
2
Orange
X2
3
Red Y1
4
ON
Brown
Y2
5
Maximum
10 m
(32 ft) Field supplied
AT-50A
X1 X2 Y1 Y2
Prohibit
OFF Permit