Mitsubishi Electric GB-50A Instruction Book page 10

(A) Level signal
① When the level signal is selected, the operation (only ON/OFF operation) for the central controller and
the local remote controller are prohibited (except during normal operation).
② When the emergency stop/normal operation signal is selected, the status will be changed from normal
operation to emergency stop when the external input signal contact turns OFF to ON, and will be
changed from emergency stop to normal operation when external input signal contact turns ON to OFF.
Emergency stop signal will bring the air conditioners to stop, and canceling the emergency stop will not
automatically restart these units. To go back to the previous operation status, they must be manually
turned back on.
③ When ON/OFF input signal is selected, the status will be changed from OFF to ON when the external
input signal contact turns OFF to ON.
(B) Pulse signal
①Even if the ON signal is input during ON, the status will remain at the ON status.
②When the local remote controller is prohibited, the ON/OFF operation, operation mode selection and
temperature setting from the local remote controller is prohibited.
③Set the pulse width (contact ON time) to 0.5 to 1.0 second.
4-2 External output function
(1) The function of external output
●The "ON" signal is output when one or more air conditioner are in the ON operation.
●The "Malfunction" signal is output when one or more air conditioner malfunctions.
(2) Specification of external output interface
CN2
No. 1
No. 2
No. 3
Lead wire
Green
Black
Brown
Description of each terminal
Common (0V)
ON/OFF
Malfunction/Normal
9