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SainSmart 4-channel 5V USB Relay Board Module Controller For Automation Robotics

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SainSmart 4-channel 5V USB Relay Board Module Controller For Automation Robotics

SKU:20-018-910 | UPC:6955170898725

This is USB controlled relay module with 4 relays SRD-5VDC-SL-C. You may use it for simple ON/OFF switching electrical devices - home lights, DC motors, solenodis and others. It may help you building projects like robotics and home automation. Each such board requires one USB port. The more USB ports you have the more Relay boards you may connect.

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  • 4 SPDT relays SRD-5VDC-SL-C
  • Relay specification – 10A 250VAC/10A 125VAC/10A 30VDC /10A 28VDC
  • Power Supply - 5 VDC
  • Current consumption - 200 mA
  • FT245RL. Datasheet –( http://www.ftdichip.com/)
  • Led for each relay output
  • Power Led
  • USb led
  • Size - 101*40*16mm
  • Windows software examples: VB6, BCB6, Java (netbeans), VB.NET 2010 Express, C++.NET 2010 Express
  • PCB parameters: FR4 / 1.5mm / two layers / metalized holes / HAL / white stamp / solder mask
  • Extra PCB openings for better voltage isolation
  • Doubled high current tracks



  • When the board is connected to the PC and the PC is restarted, the relays will be toggled several times. This is because of the structure of the FTDI chip.
  • The device must be supplied with 5 VDC or order to work.
  • There is no protection against reversed voltage! If the VCC(+5V) and GND are reversed the board will be damaged!
  • The board can not work without computer


Supply Characteristics:

Type     SRD-5VDC-SL-C
Recommend voltage   VDC 5
Voltage limits Including ripple VDC 4...7
Nominal input current Voltage 5VDC mA 300
Power dissipated When all relays are ON W 3.6
Protection Against reverse polarity   None


Relay output:

Type     12V-T73-USB
Relay type     T73
Relay outputs count     4
Contact type     NO, NC
Current consumption 5VDC mA 30
Switching parameters
125 VAC / 28 VDC
250 VAC



Download Link

Raspberry Pi

Customer Reviews

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Good productReview by Fred
(Posted on 2/24/14)

If you need to write your own program, please check out the following command sequence that works for me.
res = FT_Open(0, &fthandle);
ftStatus = FT_SetBaudRate(fthandle, 9600);
ftStatus = FT_SetBitMode(fthandle, 15, 1);
ftStatus = FT_Write(fthandle, &data, len, &dwwritten);
D2XX Programmer's Guide

1 Item(s)

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1.SainSmart provides two delivery methods from which to choose:
   (1)STANDARD SHIPPING(Free to USA, United Kindom, Canada, Australia, Germany, France, $5 to other countries)
   (2)EXPEDITED SHIPPING($12.50 to USA, $17.99 to other countries)



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Depending on your location and the type of goods you have purchased, SainSmart.com will dispatch your items via 1 from 5 carriers. Items will be shipped from our main warehouse in China. If you prefer to have it shipped from other warehouse, please contact us via support@sainsmart.com

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China Post is economic airmail reaching most part of the world, which generally takes about approximately 20 business days to arrive. And this will reduce the risk charging by local custom.
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