Toshiba MMY-MUP0961HT6P-UL Service Manual page 87

6-2-3-3. Snowfall Fan Control
Operation
An external snowfall signal turns on the outdoor unit fan.
Terminal Input signal
ON
OFF
COOL
(SW1)
ON
OFF
The input signal is recognized during its rising/falling phase.
(After reaching the top/bottom of the rising/falling edge, the signal must remain there for at least 100 ms.)
The optional P.C. board should be connected to the header outdoor unit (U1).
COM terminals have DC12 V output with a basic insulation. Use a switch, such as a relay or photocoupler,
insulated from a controller (locally procured) for CO (Change-Over) contact or NO (normally-open)
contact. DC12 V has a current-limiting resistor of 3.3 k .
For non-voltage contacts, use a relay with minimum applicable load of DC12V,3mA or less.
6-2-3-4. External master ON/OFF Control
Operation
The system is started/stopped from the outdoor unit.
Terminal
COOL
ON
(SW1)
OFF
HEAT
ON
(SW2)
OFF
Batch-operation
• Input signal is detected in the rising edge between OFF and ON of SW1/SW2 and the control is accepted in
100 msec from the edge.
• When COOL terminals (SW1 and SW2) are simultaneously turned ON, the control turned ON first is valid,
and the control turned ON later is invalid.
CAUTION
(1) Do not turn on the COOL (SW1) and HEAT (SW2) terminals simultaneously.
(2) COM terminals have DC12 V output with a basic insulation. Use a switch, such as a relay or photocoupler,
insulated from a controller (locally procured) for CO (Change-Over) contact or NO (normally-open) contact.
DC12 V has a current-limiting resistor of 3.3 k .
For non-voltage contacts, use a relay with minimum applicable load of DC12V,3mA or less.
The optional P.C. board should be connected to the header outdoor unit (U1).
Header outdoor unit
Connection
Outdoor unit
cable
interface PCB
CN509
SW1: Snowfall detection switch (snowfall sensor)
Operation
Snowfall fan control
(Turn on outdoor
unit fan)
Normal operation
(Cancels control)
Header outdoor unit
Connection
Outdoor unit
cable
interface PCB
CN512
SW1: Operation input switch
SW2: Stop input switch
Input signal
It does not matter whether the state is ON or
100ms
OFF after 100 msec from the signal input.
Batch-
operation
accepted
100ms
Batch-stop
Locally procured
Optional PCB
TB1
COM
COOL
PJ17
HEAT Shield
wire
Locally procured
Optional PCB
TB1
COM
PJ17 COOL
HEAT
Shield
wire
Turns on all indoor
units
Turn SW1 OFF before sending
Turns off all indoor
units
Batch-
stop
accepted
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Snowfall sensor
SW1
SW1
SW2
Operation