Relays
A relay is an electrical device that distributes power based on an order issued by the control part. In this way, a relay allows the opening and closing of an electrical power circuit based on logical information. The primary function of relays is most often to separate the control circuits from the power circuits for isolation purposes, e.g. to drive a high voltage or current from a lower control, and in some applications also to ensure operator safety. Although it may sound complicated, it is one of the principles of eclectic networks and can help us understand how electronic gadgets work on connectivity. In this section of the Botland store you can find many relays that will help you to explore the secrets of this learning and help you gain the right skills. If you have any questions or concerns, do not hesitate to contact our technical department. We are happy to share our knowledge and experience.
Numato Lab - 8-channel relay module 12V 7A / 240VAC + 10GPIO - Ethernet
The module has eight KT-603 relay with a coil supplied with voltage of 12 V. The system is controlled via Web interface or TELNET. In addition, the module has 10 GPIO pins...Numato Lab - 8-channel relay module 12V 7A / 240VAC + 1GPIO - Bluetooth
The module has eight KT-603 relays with a coil supplied with voltage of 12 V. The system is controlled via a Bluetooth interface. In addition, the module is equipped with 1...Numato Lab - 2-channel relay module 12V 7A / 240VAC + 8GPIO - Bluetooth
The module has two KT-603 relay with a coil supplied with 12 V voltage. The system is controlled via a Bluetooth interface. In addition, the module has 8 GPIO pins working as...Coolseer WiFi and RF Breaker - relay 230V WiFi + RF 433MHz - COL-BSW02W
Ready-made module to control 230 V to 2300 W home appliances from anywhere in the world via WiFi using a dedicated application, radio at 433 MHz or via voice commands. Quick...Coolseer WiFi Switch Module - 230V WiFi relay - COL-SM01W
A ready-made module to control 230 V to 2300 W home appliances from anywhere in the world via WiFi with a dedicated application or via voice commands. Small dimensions...Inveo LanTick Pro PE-4-4 - IoT relay module
Inveo modules allow remote control of devices via Internet. It has 4 relay outputs of 250V and 4 digital inputs operating. The module is controlled through the built-in WEB...2 Channel USB Powered Relay Module
The module has two relays KT-450 with a coil with a 5V voltage. The circuit is operated directly from the USB connector. In addition, the module provides 4 GPIO...Numato Lab - relay module 1 channel - 1A / 120VAC contacts - 5V + 4GPIO coil - USB
The module is equipped with one KT-450 relaywith a coil suppied with voltage of 5 V. The system is controlled directly from the USB connector. In addition, the module provides...Inveo LanTick Pro PE-2-2 - IoT relay module
Inveo modules allow remote control of devices via Internet. It has 2 relay outputs of 250V and 2 binary inputs operating in counter mode. The module is controlled through the...Inveo LanTick Pro PE-8-0 - IoT relay module
Inveo modules allows remote control of devices via Internet. It has 8 relay outputs of 250V and a built-in WEB server. It is adapted for mounting on a DIN rail.Grove - Solid State Relay - module with SSR 250VAC / 4A relay
Module from the Grove series with the SSR relay module with a control voltage of 3.3 V or 5 V and the maximum contact voltage of 250 V AC and 4 A. Thanks to the application...Inveo - MODBUS RFID reader - Unique 125kHz with relay
Inveo module for reading data from RFID devices in the Unique 125 kHz stadard. In addition, the reader is equipped with a 250V/5A relay. Connection via RS485 and USB ports. The...- Reduced price
- On sale
Semiconductor relay SSR-80A 480VAC / 80A - 32VDC
Solid state relay, single-phase SSR with the AC voltage of 480 V and constant of 32 V. Rated current is 80 A. The device does not create noise when switching.Semiconductor relay SSR-100A 480VAC / 100A - 32VDC
Solid state relay, single-phase SSR with the AC voltage of 480 V and constant of 32 V. Rated current is 100 A. The device does not create noise when switching.Relay module 4 channels + Bluetooth 4.0 BLE - 10A / 250V contacts - 5V coil
The module has four SRD-05 relays with a coil powered with the voltage of 5 V, it was also equipped with a module Bluetooth 4.0 BLE allowing ot control the devices via Android...Numato Lab - 16-channel relay module 24V 7A/240VAC + 10 GPIO - USB
The module is equipped with 16 relays with a 24 V coil and a 7 A / 240 V contact rating. Additionally it is equipped with 10 GPIO pins, including 5 analogue inputs with...Coolseer WiFi Breaker - relay 230V WiFi + RF 433MHz - COL-BSW01W
Ready-made module to control 230 V to 2300 W home appliances from anywhere in the world via WiFi using a dedicated application, radio at 433 MHz or via voice commands.Three-phase Solid state relay SSR Hoymk D4825HK 3x25A 380VAC / 32DC
The Hoymk D4825HK three-phase relay is made in semiconductor technology and controlled with voltages from 3 V to 32 V DC. The maximum output voltage is 380 V.DFRobot Gravity - relay 1 channel - 277VAC / 16A contacts - 5V coil
Module with relay that allow for the control of the actuators through the ports of the microcontroller. The kit includes a cable adapted to DFRobot IO Expansion Shield.MPI-S-224-C-4 relay - 24V coil, 2x 8A / 250VAC contacts
Coil voltage: 24 V, contacts: 5 A / 250 V AC. Dimensions: 29 x 12.7 mm, height: 15.7 mm.MPI-S-124-A-3 relay - 24V coil, 16A / 250VAC contacts
Coil voltage: 24 V, contacts: 16 A / 250 V AC. Dimensions: 29 x 12.7 mm, height: 15.7 mm.Relay MCB-S-224-C-S - 24V coil, 2x 1A / 125VAC contacts
Coil voltage: 24 V, contacts: 1 A / 125 VAC. Dimensions: 20,2 x 10 mm, height: 11.5 mm.Remote controller 12/24V DC - 433.92Mhz - 2 channels
The radio receiver allows you to control 2 devices operating at 250 V AC via NO/NC relay outputs. The module operates at 433.92 MHz, 2 remote controls are included to control...Transistor switch with adjustable delay - 15A / 36V
The module equipped with transistors powered with the voltage from 5 V to 36 V. T he system allows you to control actuators using microcontroller ports or any development...What are the relays used for?
The primary function of the relays is usually to separate the control circuits from the power circuits for isolation purposes, e.g. to drive a high voltage or current from a lower control, and in some applications also to ensure operator safety. Relays were mainly used in very large quantities in electromechanical PSTN telephone switching systems; they are still used, but to a lesser extent as they have been replaced by electronics and computers. Relays can also be used to create suitable logic functions, as was the case with the first computers or in pinball machines. This is still the case in many signal boxes, designed before the 1990s. Relays were used in very large quantities in electromechanical PSTN telephone switching systems; they are still used, but to a lesser extent because they have been replaced by electronics and computers in today's switches. The service life of low-end electromagnetic relays is relatively short due to wear and tear on the contacts during repeated switching. However, there are solutions to extend the life of these relays. Some relays are designed and tested to withstand a minimum of 10 million operations.
Evolution of the electromechanical relays
The fully electronic, solid-state relays advantageously replace the electromechanical relays in many situations. Why is that so? Better switching speed, quiet operation, insensitivity to vibrations, are some of its advantages over electromechanics. On the other hand, it can poorly withstand high short-circuit currents, even though it is generally equipped with internal protection. It cannot be used either as a safety cut-off, because of the leakage current and the permanent short circuit that can be generated when the component flashes (unlike the electromechanical relay which sometimes "sticks" but, most often, opens when the current returns to zero). Several so-called "safety" relays are designed to offer a guarantee of opening in the event of a failure. For fixed railway applications (signaling) these relays must usually comply with certain standard which depend on the country. Most railway networks use relays of a very similar design. The search for alternative solutions using solid state relays has not been successful so far because the probabilities of the different failure modes are too close.
Which type of relay to choose?
The electromechanical relay, by its switching principle, is similar to a mechanical switch whose operation would not be manually, but from the power supply of a coil called excitation coil or control coil. The coil excitation field creates a magnetic field even when it is traversed by a weak current. It then causes the opening or closing of a switch connected in series in a circuit containing a motor or a lamp, consuming a high current. This is why it is called power adaptation because the relay can control a power greater than the excitation power. Most of the time, it will be associated with a transistor. On the other hand, a solid state relay has no moving parts. The transmission of information is carried out by infrared using photo-triac, phototransistor or photodiode associated with a control circuit. This absence of moving parts gives it a longer life and an absence of noise during use. If you have questions or concerns, please contact our technical department. The topic of relays may seem complicated, but we will be happy to share our experience with you and advise you on the best solution for your situation.