Snowfall Fan Control; External Master On / Off Control - Toshiba MCY-MHP0305HT-C Service Manual

7-3-4. Snowfall fan control

Outdoor unit
Outdoor unit
interface PCB
SW1: Snowfall detection switch (snowfall sensor)
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.)

7-3-5. External master ON / OFF control

Outdoor unit
Outdoor unit
interface PCB
SW1: Operation input switch
SW2: Stop input switch
Operation
The system is started / stopped from the outdoor unit.
Terminal Input signal
ON
COOL
(SW1)
OFF
ON
HEAT
(SW2)
OFF
The input signal is recognized during its falling phase. (After reaching the bottom of the falling edge, the signal must
remain there for at least 100 ms.)
CAUTION
(1) Do not turn on the COOL (SW1) and HEAT (SW2) terminals simultaneously.
(2) Be sure to provide a contact for each terminal.
External signal: No-voltage pulse contact
Connection
Optional PCB
cable
C N 5 0 9 P J 1 7
Operation
Snowfall fan control
(Turns on outdoor
unit fan)
Normal operation
(Cancels control)
Connection
Optional PCB
cable
COM
COOL
C N 5 1 2 P J 1 7
HEAT
Operation
Turns on all indoor
units
Turns off all indoor
units
35
58
Locally procured
Snowfall sensor
TB1
COM
COOL
SW1
Shield
HEAT
wire
Locally procured
TB1
SW1
SW2
Shield
wire