Introduction
IoT communication protocols are methods of communication that secure and maintain the highest level of security for data sent between connected devices.
The Internet of Things devices is often linked to the Internet over an IP (Internet Protocol) network. Bluetooth and RFID, on the other hand, enable IoT devices to communicate locally. There is a variation in power, range, and memory employed in these circumstances.
Connections over IP networks are more complicated, necessitating more memory and power from IoT devices, whereas range is not an issue. Non-IP networks, on the other hand, use less power and memory but have a shorter range.
In this blog, we will learn about Relay Modules, its working as well as its advantages and disadvantages in IoT development.
What is Relay in IoT Development
A relay is identical to a light switch on an electrical circuit. Raise the switch to turn on the light. Lower the switch to turn off the light. A light switch closes (or completes) an electrical circuit to turn on a light, and it simply opens (or breaks) the circuit to turn it off. A relay performs the same purpose as a switch, except that a low-power signal controls the switch. As seen in the two images below, different relays exist, each with its unique set of poles and throws.
What do you mean by Pole and Throw?
Pole and throw relate to how many inputs and outputs there are. Single Pole Double Throw (SPDT) relays are a frequent form of a relay. There is one incoming path and two possible outbound paths depending on the low-level incoming signal. The "usually closed" way is one of the paths; it signifies that the circuit is closed without power. The other way is "usually open," which means the circuit is open when no power is provided. Figure 3 depicts the many poles and throw options available for relays.
Need For Relay Modules
Relays are used for a simple purpose. High-powered circuits, such as lamps or lights, cannot be switched by an Arduino or Raspberry Pi. These devices usually feature 5v or 3v connectors and no additional means of switching circuits. Relays may also be used to switch existing circuitry in your home without causing too much change, such as a sprinkler system. Water sprinkler wire has previously been run to a place. Connect the solenoid valve wires to the existing power and operate your sprinklers using the relay and an Arduino. It's that easy! then switching on the light
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