Panasonic CS-A18BD3P Service Manual page 55

1. Automatic address setting (no need to have dip-switch set)
If the wiring connected properly as above example, the address is set automatically by the main power supply. An indoor unit
with remote control will be set as the master. If the power source is installed to indoor units and outdoor separately, turn on the
switch as the following procedure: outdoor unit, indoor unit with control, and other indoor units.
When the slave units do not operate (when address cannot be set)
Important: The address for the group control cannot be reset, using the above mentioned procedure.
2. Manual address setting (by dip-switch DSW1)
When you set the address manually, set the dip-switch of the PC board in the indoor unit as follow:
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