Panasonic U-8MF2E8 Service Manual page 28

5. Outdoor Fan Control
5-1-2. Snow Removal Control
(1) Independent control of outdoor unit（control for fan crack prevention）
This control is intended to prevent snow from accumulating on stopped fans.
When the outdoor unit is stopped, the fan motor is forcibly started by the control for fan crack prevention's fan
mode.
Fan motor operates for 45 seconds and stops for 2 hours when ambient temperature is 5.1°C or more.
Fan motor operates for 45 seconds and stops for 1.5 hours when ambient temperature is 0.1 ~ 5.0°C.
1
Fan motor operates for 45 seconds and stops for 1 hour when ambient temperature is 0.0°C or less.
(2) Control with snow detection sensor (Field supply)
If a snow detection sensor (field supply) is available, the snowfall-protection hood might be unnecessary
excluding heavy snow region.
When set in this mode, the fan motor is forcibly started by the snowfall sensor control's fan mode.
One snow detection sensor can control all outdoor units on the communications wiring.
The snow detection sensor must be connected to one of the main units (unit No.1) and it can control all outdoor
units in communication wiring.
* To activate this function, it is necessary to set it to all EEPROMs on outdoor PCBs.
CODE: 04
Setting
No.
Snow detection sensor is NOT connected with this unit.
But this function is performed according to the signal of the sensor connected with other outdoor
0
unit.
(Factory preset mode)
1
Snow detection sensor is connected with this unit.
And this function is performed according to the sensor signal.
Snow detection sensor is NOT connected with this unit.
2
And this function is NOT performed.
Snow detection sensor is connected with this unit.
3
But this function is NOT performed.
Snow detection sensor
Unit No. 1
Setting No.
Fan motor state
in case of snow
System address 1
Unit No. 2
Unit No. 3
1 0 0
ON ON ON
* All main outdoor units are connected with same communication wiring.
Operation
System address 2
Unit No. 2
Unit No. 1 Unit No. 3
0 0 0
ON ON ON
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3WAY SYSTEM
Control Functions
System address 3
Unit No. 2
Unit No. 1 Unit No. 3
2 2 2
OFF OFF OFF