SR-104A Serial Port Control 2-way Relay Module Delay Relay Single Chip Microcomputer Controller Finished Board

Description The improved SR 104 module adopts patch technology and supports 5V or 9 12V input voltage The pull in and release of two relays are controlled by serial command and each channel is independently set with a delay of 1 255 seconds The operation is simple and most serial instructions only need 1 byte to realize their functions Provide VB upper computer program and source code to realize computer remote control more easily After receiving each instruction the module will return to the latest status of all relays In addition the module can also respond to the relay status query from the upper computer program The upper computer program can judge whether each operation is successful or not through these feedbacks from the module and improve the accuracy of control SR 104A can be extended with a MO 94C 2 relay module to control 4 relays through serial port Specifications Power requirements DC 4 5 V 5 V positive inside and negative outside Or DC9 12V PCB dimensions length 71mm x width 47mm Features 1 STC15F104W as the main control chip 2 Each channel is independently set with a delay of 1 255 seconds 3 The operation is simple and most serial commands are single byte commands 4 Onboard 2 way relay5 Relay with absorption diode circuit6 Each channel has an LED indicator light and the relay is engaged when the light is on 7 An MO 94C module can be extended to control four relays through serial port 8 With 1 power indicator lamp9 The work stabili