Shenzhen Ganrey Technology LED Strip screen control card serial protection explain:

1 . Disable connected directly to 220V voltage to the LED display control card (control card input voltage is 4.5 ~ 6V)

2 serial cable to avoid live waiting, so as not to supply instant impact. For pluggable, power LED display control card can operate.

3 .to avoid the LED on the control card devices and welding foot contact with other metals in order to avoid short-circuit

4 should measure the serial port status to negative is connected to ground, not to the positive and negative phase.

In the case of correct specification of the LED control card, still can not communicate, you can press the following checks:
1 using the serial cable is straight-through cable serial cable (parallel)
2 serial interface is loose
3.LED control card is powered
4.USB to serial cable support your computer system, driver installation is solution