Led Indicators - Quatech USB to RS-232/422/485 Isolated Converter SSU2-400I Operation Manual

LED Indicators

SYS (Red)
It is a power indicator (When the power is on, the SYS LED will be on.)
RX (Orange)
Data received indicator (When data are received from the USB, the RX LED
will be on.)
TX (Green)
Data sent indicator (When data are sent out to the USB, the TX LED will be
on.)
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