Mitsubishi Electric PUHY-P250YNW-A Service Handbook page 112

[5-3 Indoor Unit Control ]
-7- Switching Between Pulse and Level of MA Remote Controller External Input
The start/stop operation can be performed by either of the MA remote controller or the external input (pulse/level).
DIPSW on the address circuit board (No.1 and No. 2)
SW1-10 = OFF
SW1-10 = ON
* The manipulator for centralized control can be operated regardless of the SW1-9 status (ON),
and SW1-10 status (OFF).
* For the MA remote controller and the external input, the operation command sent later has no priority.
* When the Normal/Inspection switch on the main unit is set to "Inspection", the external input will be disabled.
Only the operation performed by the MA remote controller is valid.
Input
Function
Start/Stop
* Use a contact point for small electrical current (12V DC 1mA).
External input-output
board (IFB)
AC
TB23
A1
A2
BC
TB21 B1
B2
-8- Operation during Electrical Power Failure
After the controller in this air conditioning unit receives signals indicating power failure or an instantaneous
drop in voltage, unless the unit receives a command not to restart, it will resume its operation after power
supply is restored.
Depending on the duration of power outage, the following operations will be run.
Duration of Power Outage
Shorter than 6msec
Longer than 6msec and
Shorter than 50msec
(Note1, Note2)
Longer than 50msec
(Note1, Note2)
Note 1: When indoor unit is in the maintenance mode , it will not resume operation even after the power has
been restored.
Note 2: After the unit resumes its operation, MA remote controller will display 'HO' for fifteen seconds, during
which time the MA remote controller will not respond. To turn off the unit during this time, turn off the
power with an electric leak breaker.
BS_05_C
SW1-9 = OFF
SW1-9 = ON
Usage
Pulse (With-voltage/No-voltage a-contact) *
Sending ON/OFF
<In case of with-voltage>
command to the
Power supply:12~24V DC Electrical current:10mA (12V DC)
indoor unit
<Pulse specification>
(Pulse powering time) (Pulse interval)
When using the external input function on the indoor unit
that is connected to a two-refrigerant circuit, connect the
short-circuit plate that is supplied with the unit to the
appropriate terminals on the external input-output board.
A
The case of with-voltage input ... A
The case of no-voltage input .... B
B
Both indoor and outdoor units will stay on.
It is recognized by the unit as aninstantaneous power outage
Indoor Unit: The fan stays on.
Outdoor Unit: Compressor stops, then resumes its operation 20 seconds later.
It is recognized by the unit as power outage.
Air-conditioning unit will stop (incl. fan and compressor).
It will resume operation after the power has been restored.
* The time it takes for the indoor unit fan to resume its operation after power failure is as follows:
20 seconds + (indoor unit address/2) seconds (55 seconds max.).
* The compressor on the outdoor unit will resume its operation according to the operation signal
from the indoor units after 30 seconds since power restoration.
Valid operation
External input (level)
External input (pulse)
MA remote controller
Signal specifications
over 200ms over 200ms
Unit Operation
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chapter 5 -