LG GLOFA-GM Series User Manual page 317

Chapter 8 Exercising program
Consequently, If 8 LEDs of master station are turned on, 8 LEDs of slave station are turned off.
And if 8 LEDs of master station are turned off again, 8 LEDs of slave station are turned on.
Surely set both master / slave stations to "Communication Enable" to start communication.
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