– 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.)
(2) Level signal and pulse signal
(A) Level signal
(B) Pulse signal
(3) External input specifications
(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
Mode
External input signal setting
Notes
1
Do not use external input. (Factory setting)
–
2
Emergency stop/Normal operation signal (level
signal)
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.
3
ON/OFF signal (level signal)
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.
4
ON/OFF and Prohibit/Permit remote controller
operation signal (pulse signal)
The ON-signal pulse width should be set to a value between 0.2 and 1 seconds.
CN2
Lead wire
Emergency stop/Normal
operation signal (level signal)
ON/OFF level signal
ON/OFF, Prohibit/Permit remote
controller operation (pulse signal)
1
Green
Built-in 5 VDC power for external input * Exclusively for use with external input. Not usable for other purposes.
2
Yellow
Emergency stop/Normal operation
signal input
ON/OFF signal input
ON signal input
3
Orange
Not used
Not used
OFF signal input
4
Red
Not used
Not used
Prohibit-local-remote-controller-
operation signal input
5
Brown
Not used
Not used
Permit-local-remote-controller-
operation signal input
(A) Level signal
(B) Pulse signal
*Same for Prohibit/Permit remote controller operation.
Contact ON
Contact OFF
Contact ON
Contact OFF
Contact ON
Contact OFF
Contact ON
Contact OFF
ON
OFF
OFF
ON
OFF
OFF
(ex.)ON/OFF
Signal 1 (ON)
Signal 2 (OFF)
0.2 to 1 seconds
0.2 to 1 seconds
Normal
operation
Normal
operation
Emergency
stop
CN2
X1
AT-50A
X1
1
2
3
4
5
Maximum
10 m
(32 ft)
Field supplied
Yellow
Green
ON/OFF
or Emergency stop
X1
X2
Y1
Y2
CN2
X1
AT-50A
X2
Y1
Y2
1
2
3
4
5
Orange
Maximum
10 m
(32 ft)
Field supplied
Brown
Red
Yellow
Green
Prohibit
ON
Permit
OFF
