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Crowtail- Solid-State Relay


Crowtail- Solid-State Relay is a non-contact electronic switch module that has relay features.It has a maximum output of 240VAC/4A, with a switching speed less than 10ms. The featured LED indicates that the relay is on. It can be widely used in various areas such as computer peripheral interfaces, temperature/speed light adjustment, servo control, petrochemical, medical instrumentations, financial devices, coal, meters, traffic signals, etc.
Model: CT009739R

Crowtail- Solid-State Relay.jpg


  • Compatible with both 3.3V and 5V control level
  • Low switching latency(≤10ms)
  • LED on-state indicator
  • Level trigger
  • Crowtail compatible
  • Dimensions(mm):40.0(L)x20.0(W)x22.9(H)

Application Ideas

  • Operations that require low-latency switching, e.g. stage light control
  • Devices that require high stability, e.g. medical devices, traffic signals
  • Situations that require explosion-proof, anticorrosion, moisture-proof, e.g. coal, chemical industries.
  • For all Grove users (especially beginners), we provide you guidance PDF documents. Please download and read through Preface - Getting Started and Introduction to Grove before your using of the product.


1.Trigger signal voltage:

  • Low level: 0-1.5 V the relay ON
  • High level: 2.5-5 V the relay OFF

2.Connect Crowtail- Solid-State Relay to port D2(one button to D5) of Crowtail - Base Shield and plug it into Arduino/Crowduino.

20160531 1113071.jpg

3.Copy and paste code below to a new Arduino sketch, and upload it to your Arduino.

 int relay=2;
 int buttonPin=5;
 int buttonState = 0;
 void setup ()
   pinMode(buttonPin, INPUT); 
 void loop()
        buttonState = digitalRead(buttonPin);
         if (buttonState == HIGH) {     

    digitalWrite(relay, LOW);  
  else {

    digitalWrite(relay, HIGH); 

4.When upload the code complete. Press the button, the yellow indicator light turns on , Relay on. Loosen the button, indicator light off and relay is off yet.