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With reference to the current international health situation we confirm the normal activity of our company. There will be no delay in shipments and the workflow will remain as it has been.
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RS232 Serial COM controlled 4 Channel Relay Board BOX

The general purpose of the Relay Controller is connection to a PC's RS232 COM port. Control devices using your PC.
  • Code: SS_R2S4CR
  • Manufacturer:
  • In stock: 975

Price: €33.00



- One RS232 4 Channel Relay Board

Required power:
Allows power supply voltage from 9 to 24V DC


- Each relay has an LED to indicate when it is operated.
- Relay outputs can be used to turn ON/OFF lights, motors and other devices.

Relays have Normally Open (NO) and Normally Closed (NC) Contacts
each capable of switching max:
- 12VDC/15A
- 24VDC/15A
- 125VAC/15A
- 250VAC/10A


User Manual:
RS232_Four_Channel Relay Box.pdf

Communication Parameters:
8 Data, 1 Stop, No Parity
Baud rate : 9600

FIRST chanel commands:
OFF command : FF 01 00 (HEX) or 255 1 0 (DEC)
ON command : FF 01 01 (HEX) or 255 1 1 (DEC)

SECOND chanel commands:
OFF command : FF 02 00 (HEX) or 255 2 0 (DEC)
ON command : FF 02 01 (HEX) or 255 2 1 (DEC)

THIRD chanel commands:
OFF command : FF 03 00 (HEX) or 255 3 0 (DEC)
ON command : FF 03 01 (HEX) or 255 3 1 (DEC)

FOURTH chanel commands:
OFF command : FF 04 00 (HEX) or 255 4 0 (DEC)
ON command : FF 04 01 (HEX) or 255 4 1 (DEC)


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How to control USB relays - Windows Shortcut example, Windows Command Line example, Macintosh example, Abacom ProfiLAB example, Sample Visual Basic code, Sample C# code, Sample PHP files and more




Additonal information

  Payment accepted:
Credit Card payments, PayPal

Bank Wire Transfer

We ship WORLDWIDE through TNT.

  Import duties, taxes and charges are not included in the item price or shipping charges. These charges
are the buyer's responsibility. Please check with your country's customs office to determine what these additional
costs before you purchase.

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