2-channel 5V Relay Module with Optocoupler (HCARDU0043)

Relay modules designed for interfacing to microcontrollers.
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2-channel 5V Relay Module with Optocoupler (HCARDU0043)

Post by admin » Wed Dec 18, 2013 2:45 pm


This is a 5V 2-Channel Relay interface board, which enables control of various appliances and other equipment with large current. It can be controlled directly by a Microcontroller (Arduino, 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic).


5V 4-Channel Relay interface board, each requires 15-20mA Driver Current
Standard interface that can be controlled directly by microcontroller (Arduino, 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic)
Equipped with high-current relay, AC250V 10A ; DC30V 10A
Indication LEDs for Relay output status
Equipped with screw holes for easy installation



Can I connect this module to the 3.3V digital IO pins of my Raspberry Pi, Due, etc...?

The module should be safe to connect 3.3V development boards that do not have 5V tolerant DIO. Although the module is powered from a 5V source, each of the two digital 'IN' pins are connected in series to an opt-isolator and an indicator LED. Due to the forward voltages required by the opt-isolator LED and the indicator LED to allow them to conduct, you should only see about 3V at the IN pins when they are not grounded. The only thing to check is when energising the relays by grounding these pins there will be about 2-3mA of current flowing into each DIO pin. You should check that your development board's IO cells are capable of sinking this amount of current which in the case of this 2 channel relay will be between 4 to 6mA when both relays are in the energised state (IN1 & IN2 low). For an Arduino due this is fine, but for a Raspberry Pi, this is software configurable and depends on it's source/sink DIO current setting.

How do I power the module?

The module requires a 5V supply which should be connected to right most pin marked VCC for positive, and GND for negative (0V). There is a small tolerance for this supply which is limited by tolerance of the relays of ~ 4.4V to 5.5V.

What is the ID-VCC pin for?

This pin should have a jumper on it connecting it to VCC by default. It is simply there to provide the option of separating the 5V supply to the relays so they can be powered from a separate isolated power supply.

How do I energise the relays ?

Applying GND to either of the IN terminals should energise the appropriate relay (power to VCC and GND must also me connected of course). Disconnecting the pin or pulling the pin to 5V will de-energise the relay.

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