This post contains affiliate links. As an Amazon Associate we earn from qualifying purchases.
Our picks are based on Amazon bestseller rankings, verified customer ratings, and product availability. We update our recommendations regularly to ensure accuracy.
PC board relays are essential components in electronic circuits, acting as electrically operated switches. Selecting the correct relay ensures reliable operation and longevity for your electronic projects and devices. Understanding the key specifications will help you make an informed decision for your specific needs.
5V Relay Module: Working Voltage: DC 5V; Maximum Load: AC 250V/10A, DC 30V/10A; Trigger Current of Opto-Isolator: 5mA
Fault-Tolerant Design: Fault Tolerant Design, Even if the Control Line is Broken, the Relay will not Operate;All Interfaces of Relay can be Wired Out Through the Terminals Directly,Normally Open and Normally Closed
Optocoupler Isolation:1 Channel Relay Board use Optocoupler Isolation that has Strong Driving Ability and Stable Performance ,The Isolation Circuit Prevent Damages to I / O Port by Relay Switch Current
Jumper Design: The Relay Module has a Jumper That You Can Set Rather the Unit State Changes with High or Low Signal. Has Screw Terminals for Relay (NC,C,NO) and for Input; Coil +, Coil - and Trigger.
Wide Application: DC 5V Relay Module Works Well with ARM /PIC /AVR /MCU/Raspberry/CNC Machine/ PS4 etc.
It is 4 Channel Isolated 5V 10A Relay Module, each relay can individually switch on/off by an opto-isolated digital input, Standard interface can be directly connected with microcontrollers and be controlled directly by a wide range of microcontrollers...
Equipped with high-current relay, maximum load: AC250V 10A, 15A 125VAC, DC30V 10A; Trigger current of opto-isolator: 5mA.
RELIABLE: Fault-tolerant design, even if the control line breaks, the relay will not move; With optical coupling isolation, triggering more reliable, more stable.
EASY to INSTALL: Equipped with screwed terminal plate and fixed bolt holes(diameter: 3.1 mm) on both sides for easy installation.
High/Low level trigger can be selected by jumper. Very versatile, you can reverse the input logic with the jumper.
The module uses HID technology, without any driver, plug and play. Support WIN7, 10,XP 32-bit, 64-bit system, easy to use simple.
Onboard square USB interface, stable connection; use of high-performance USB control chip; use dedicated relay driver chip ULN2803, relay work more stable;
Power outlet and terminal, two access power mode convenient and flexible. After connecting the power, even if the computer shut down or USB from the computer pull out, the relay can also maintain the set state.
【NOTE: The 1-Channel 2-Channel module does not require an external power supply. 4-Channel 8-Channel modules require an external module power supply. 】
AC voltage maximum load 250V, AC current 10A, DC voltage maximum load 30V, DC current 10A, output normally open or close
MAIN FUNTION : Support all MCU control, industrial field, PLC control, smart home control, VCC system power supply, etc.Strict quality control and quality assurance, high safety factor, can be used with peace of mind.
AC voltage maximum load 250V, AC current 10A, DC voltage maximum load 30V, DC current 10A, output normally open or close
Small size, easy to carry and store, easy to use and with good performance
Application: The relay module supports all MCU control, industrial field, PLC control, smart home control, VCC system power supply, etc.
COMPATIBLE WITH MILWAUKEE M18 BATTERIES: Specifically designed for 18V 10-cell 21700 battery packs, including Milwaukee M18 6.0Ah and 8.0Ah models, ensuring a perfect fit for your DIY battery repairs and upgrades.
ENHANCED PROTECTION CIRCUITRY: Features an advanced PCB that provides overcharge, over-discharge, short circuit, and overheating protection, extending the lifespan and safety of your battery packs.
IDEAL FOR DIY REPAIRS & UPGRADES: A cost-effective solution for professionals and hobbyists looking to repair or upgrade their Milwaukee M18 batteries, providing reliable performance.
DURABLE & RELIABLE CONSTRUCTION: Made with premium materials for lasting durability, this protection circuit board ensures optimal performance in both professional and home-use environments.
VALUE 2-PACK: Includes two PCBs, giving you the flexibility to repair or upgrade two battery packs, or to keep a spare for future projects.
Product Description: 5v relay module's maximum load of the normally open interface: AC 250V/10A, direct current 30V/10A, with trigger current 5mA; It is featured with stable performance and sensitive reaction to make sure a satisfactory using demands
Large Quantity: you can receive 24 pieces of relay boards from the package, sufficient in quantity, exquisite in workmanship, enough for you to use, replace and share with your family and others
Stable and Functional: equipped with SMD optocoupler isolation, relay switches are powerful in drive ability, safe and reliable to use, and they can support high level or low level triggers, which can well facilitate your use
Fault Tolerance: relay module is designed with good fault tolerance, the relay doesn't act even if the control line is disconnected, which is an intimate and thoughtful design for you; And you can connect all interfaces through the wiring terminal, saving...
Size and Compatibility: 5v relay 1 channel measures about 50 x 26 x 18 cm/ 19.69 x 10.24 x 7.09 inches, convenient for your installation and storage; And they are compatible with PIC, ARM, CNC Machine and so on, versatile to use
Fully-Sealed PCB Relay: The G8P-1A4P relay is fully-sealed, providing excellent protection against dust, moisture, and other environmental factors. It is designed for reliable performance in various applications, including PC board or panel-mounted...
High Current Rating: With a robust current rating of 30A, this relay is capable of handling high electrical loads. It ensures efficient power distribution and reliable operation in demanding applications, such as solving the F01 code problem in dryers.
4-Pin Configuration: The G8P-1A4P relay features a 4-pin design, allowing for secure and efficient electrical connections. The pins are designed for easy installation on PC boards or panels, ensuring compatibility and hassle-free setup.
12VDC Coil Voltage: Operating on a 12VDC coil voltage, this relay is compatible with standard electrical systems. It provides a stable power source for efficient operation and reliable control of electrical components.
Welding Capability: The solder wire on the bottom of the relay make it easy and reliable welding. This feature ensures a strong and secure connection for optimal performance.
4 Channel Relay Module’s Path Can Be Triggered By High Level or Low Level Through Jumper Setting; Trigger Current of Opto-Isolator: 5mA
This 12V Relay Module is 4 Channel Isolated, Each Relay Can Individually Switch On/Off By An Opto-Isolated Digital Input
12V 4 Channel Relay Module Comes with High-Current Relay,Maximum Load: AC 250V 10A;AC 125V 15A ; DC 30V 10A
This Module Design With Fault-Tolerant , Even If The Control Line Breaks, The Relay Will Not Move; With Optical Coupling Isolation,Triggering More Reliable and Stable
The Module Equipped With Screwed Terminal Plate and Fixed Bolt Holes,Bolt Hole: 3.1 mm; 67*44.5mm (Spacing);Standard Interface Can Connect With Microcontrollers and be Controlled By a Wide Range of Microcontrollers Directly
Last update on 2026-07-10 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best PC Board Relays
Understanding Relay Types
Electromechanical Relays (EMRs): These are the most common type, using an electromagnet to operate a mechanical switch. They offer high current handling and isolation but can be slower and generate noise.
Solid-State Relays (SSRs): SSRs use semiconductor devices to switch loads, offering faster switching speeds, no moving parts, and longer life. However, they may have higher on-resistance and limited current capacity compared to EMRs.
Key Specifications to Consider
Coil Voltage: This is the voltage required to energize the relay's coil and activate the switch. Ensure it matches your control circuit's voltage.
Contact Rating: This includes the maximum voltage and current the relay contacts can safely switch. Choose a rating that exceeds your load requirements to prevent damage.
Number of Poles and Throws: Poles refer to the number of independent circuits the relay can control, while throws indicate the number of circuit states (e.g., Single Pole Single Throw (SPST), Single Pole Double Throw (SPDT)).
Contact Material: Different materials (like silver alloy, gold plating) offer varying levels of conductivity, resistance to arcing, and suitability for different load types (resistive vs. inductive).
Environmental Factors
Operating Temperature: Relays have a specified temperature range for reliable operation. Consider the ambient temperature of your application.
Vibration and Shock Resistance: For applications in harsh environments, look for relays designed to withstand physical stress.
Mounting and Form Factor
Through-hole vs. Surface Mount (SMD): Through-hole relays are soldered into holes on a PCB, while SMD relays are mounted directly onto the surface. Your PCB design will dictate the appropriate type.
Size and Pinout: Ensure the physical dimensions and pin configuration are compatible with your board layout.
Frequently Asked Questions
What is the difference between Normally Open (NO) and Normally Closed (NC) contacts?
Normally Open (NO) contacts are open when the relay coil is de-energized and close when the coil is energized. Normally Closed (NC) contacts are closed when the coil is de-energized and open when the coil is energized.
How do I determine the correct coil voltage?
The coil voltage must match the voltage supplied by your control circuit. Using an incorrect voltage can prevent the relay from operating or damage it.
What is a relay's switching speed?
Switching speed refers to how quickly the relay can change its contact state from open to closed, or vice versa. This is particularly important for applications requiring rapid on/off cycles.
Can I use a relay for AC and DC loads?
Some relays are designed for AC loads, some for DC, and others are universal. Always check the relay's specifications to ensure it's rated for your specific load type (AC or DC) and voltage/current.
What does 'contact bounce' mean?
Contact bounce is a phenomenon where relay contacts physically rebound and make/break contact multiple times for a brief period when switching. This can cause signal glitches in sensitive digital circuits.
How do I protect a relay from voltage spikes?
For inductive loads, a flyback diode or a snubber circuit across the relay coil or contacts can help suppress voltage spikes generated when the coil de-energizes.
As an Amazon Associate, we earn from qualifying purchases. Product prices and availability are accurate as of the date/time indicated and are subject to change.
We use cookies to enhance your experience. By continuing to visit this site you agree to our use of cookies. Read our Privacy Policy
Before You Go!
Get the latest deals and product comparisons delivered to your inbox.
