What Is a Smart Relay?
A smart relay refers to an ultra-compact programmable controller.
A programmable controller is a device that outputs from inputs such as pushbuttons and sensors based on predetermined software.
A smart relay is about as wide as several standard mini-power relays in a row. They are economically advantageous because the control panels that house them can be made smaller. However, they have the disadvantage of having fewer inputs and outputs than general programmable controllers and are less expandable.
Uses of Smart Relays
Smart relays have only four output points without expansion. As such, they are used more in commercial facilities than in factories or other large industrial equipment.
Smart relays are equipped with weekly time switches and other functions as part of their existing performance. Therefore, they are used to manage lighting, air conditioning, and refrigeration equipment in stores. They could also be used for signal indicators on private roads.
In factories, it can be used for simple devices such as controlling rainwater collection pumps.
Since the software is editable, a wide range of uses of the system can be anticipated.
Principle of Smart Relays
Smart relays are divided into three parts: a power terminal, an input terminal, an arithmetic unit, and an output terminal.
The power supply specification is selected according to the available power supply.
The input terminal is mainly used to input signals from sensors and push buttons. Both analog and digital signals can be input. For analog input, only voltage input can be selected. For current input, a resistor is connected in parallel to convert it to a voltage input. AC digital input and DC digital input can also be selected depending on the type of smart relays.
The arithmetic part stores and processes the smart relay software. It is the CPU of the programmable controller. The software can be edited both by programming software and by display panel editing. Simple software can be edited on the display panel. Complex software that includes analog signal processing is generally edited by programming software.
The output terminal is the part that outputs digital signals. Transistor output and relay output can be selected according to the type of output device.