40A Solid State Relay | Three-Phase SSR with Zero-Crossing & Thermal Protection

All Categories
EN EN

High-Performance Solid State Relay 40A for Reliable Industrial Switching

Discover the Solid State Relay 40A, a robust and efficient switching solution engineered for demanding industrial applications. Manufactured by Zhejiang Suosite Electrical Technology Co., Ltd., a national high-tech enterprise with over a decade of expertise in temperature and control instrumentation, our 40A solid state relay delivers exceptional performance, reliability, and longevity. Designed to replace traditional electromechanical relays, it offers faster switching speeds, silent operation, and superior resistance to shock and vibration. With CE certification and advanced manufacturing processes, our SSR 40A ensures precise control in diverse environments, from HVAC systems to packaging machinery. Ideal for OEM and ODM projects, this relay supports multiple control inputs and is backed by rigorous quality assurance, making it a trusted choice for global clients.
Get A Quote

Case Study

Superior Thermal Management and Long Lifespan

Our Solid State Relay 40A incorporates advanced thermal design with integrated heat sinks and efficient heat dissipation materials, ensuring optimal operating temperatures even at full load. This reduces thermal stress on internal components, significantly extending the relay's service life compared to standard SSRs. In high-cycle applications like temperature controllers or motor starters, our relay maintains consistent performance, minimizing downtime and maintenance costs. The use of premium-grade semiconductor devices and robust construction ensures reliable operation in ambient temperatures up to 80°C, making it suitable for harsh industrial settings. By choosing our 40A SSR, you invest in a durable component that reduces total cost of ownership and enhances system uptime.

Fast and Silent Switching with Zero Cross-Over Technology

Experience ultra-fast response times with our Solid State Relay 40A, featuring advanced zero-crossing detection that minimizes electrical noise and voltage spikes. This technology ensures clean switching, protecting sensitive loads and reducing electromagnetic interference (EMI) in adjacent equipment. Unlike mechanical relays, our SSR operates silently, eliminating audible clicks and vibrations, which is critical for noise-sensitive environments like medical devices or precision laboratories. The fast switching capability (on/off time <1ms) enables high-frequency control, improving process accuracy and energy efficiency. With built-in snubber circuits and overvoltage protection, our relay guarantees safe and reliable performance in inductive or capacitive loads, enhancing overall system stability.

Global Certifications and Customization Flexibility

Our Solid State Relay 40A meets international CE and RoHS standards, ensuring compliance for global markets. We offer extensive customization options, including custom input control voltages (3-32VDC, 24-380VAC), output voltages up to 480VAC, and customizable terminal configurations to fit your specific PCB or chassis mount requirements. As a manufacturer with in-house R&D and testing facilities, we provide OEM/ODM services with low minimum order quantities and fast lead times. Our technical team supports you in optimizing relay parameters for your application, ensuring maximum compatibility and performance. With a supply capacity of over 800,000 units annually, we meet large-scale demands without compromising quality. Trust Suosite for flexible, certified, and reliable solid state relay solutions.

Related products

TS Three-in-one controller VIEW DETAILS

TS Three-in-one controller

Solid State Relay DC Input 12V 24V/220/380V Three-phase JGX3 SSR-3 032 38100Z DC Control AC Module VIEW DETAILS

Solid State Relay DC Input 12V 24V/220/380V Three-phase JGX3 SSR-3 032 38100Z DC Control AC Module

Three-in-One Touch Screen TS600 Temperature Controller Hot Stamping Machine Functionality 100~240VAC Power Supply 1 Year VIEW DETAILS

Three-in-One Touch Screen TS600 Temperature Controller Hot Stamping Machine Functionality 100~240VAC Power Supply 1 Year

In industrial automation, the choice of switching components directly impacts system reliability and efficiency. The Solid State Relay 40A from Suosite offers a superior alternative to conventional relays, featuring semiconductor-based switching that eliminates moving parts, resulting in faster operation and reduced maintenance. Its compact design allows for space-saving installations, while the integrated heat dissipation ensures stable operation even under continuous heavy loads. The SSR delivers precise control with minimal power loss, contributing to energy savings and lower operating costs. Its compatibility with various load types, including resistive, inductive, and capacitive loads, makes it a versatile choice for applications such as temperature control in plastic injection molding, packaging machinery, and HVAC systems. The relay's zero-crossing function minimizes inrush currents, prolonging the lifespan of connected equipment. Additionally, its noise-free operation enhances the working environment, making it suitable for laboratory and medical equipment. With global certifications and a reputation for quality, Suosite's 40A SSR ensures peace of mind for engineers and procurement specialists. By integrating this relay into your systems, you benefit from advanced technology that meets modern industrial demands, ensuring dependable performance and long-term value.

Frequently Asked Questions

What is the maximum load current and voltage for the Solid State Relay 40A?

The Solid State Relay 40A is rated for a continuous load current of 40 amps at ambient temperatures up to 40°C (derating above this). It supports output voltages up to 480VAC, making it suitable for most three-phase and single-phase systems. For higher currents, please contact our technical sales for guidance on appropriate heat sinking or alternative models. The relay's internal semiconductor devices are selected to handle surge currents up to 800A for 10ms, ensuring robustness against transient overloads. Ensure proper thermal management by mounting the relay on a suitable heat sink with adequate airflow to maintain optimal performance and longevity. Our datasheet provides detailed derating curves and thermal impedance values to assist in your design.
Zero-crossing switching activates the output when the AC voltage crosses zero, minimizing inrush current and electromagnetic interference, which is ideal for resistive loads like heaters. Random-on switching allows instant activation at any point in the AC cycle, providing faster response for inductive loads such as motors or transformers, but may generate higher EMI. For most temperature control applications, zero-crossing is recommended. If you require precise phase control or fast switching, random-on may be necessary. Our Solid State Relay 40A offers both options; please specify your requirement when ordering. Our engineers can assist you in selecting the best configuration based on your load characteristics and application needs.
Yes, our Solid State Relay 40A can be controlled by PLCs, microcontrollers, and other digital controllers. It offers input control voltages of 3-32VDC for DC models or 24-380VAC for AC models, with an input impedance suitable for direct connection to most logic outputs. For DC inputs, ensure the control signal provides adequate current (5-20mA) to activate the internal LED. It is advisable to use a series resistor or consider the input impedance specified in the datasheet. Additionally, we offer versions with status outputs (e.g., SSR relay output) for feedback to the controller. For long cable runs, consider using shielded cables to prevent noise. If you encounter compatibility issues, our technical support can provide recommendations for interface circuits.
To operate at 40A continuously, the Solid State Relay must be mounted on an appropriate heat sink to maintain junction temperature below 125°C. The thermal resistance of the heat sink should be ≤ 1.0°C/W for ambient temperatures up to 40°C. We offer compatible heat sinks and thermal pads as accessories. In applications with lower ambient temperatures or reduced duty cycles, a smaller heat sink may suffice. It is crucial to apply thermal grease and ensure proper torque when mounting. We provide detailed thermal derating curves in our datasheet. If space is limited, consider using a forced-air cooling fan to improve heat dissipation. For high ambient environments, consult our technical team to select the optimal cooling solution.
Our Solid State Relay 40A includes built-in snubber circuits (RC network) to suppress voltage transients and dv/dt. Additionally, each unit is equipped with a varistor (MOV) across the output to clamp voltage spikes. However, for short-circuit protection, external fuses or circuit breakers are recommended. We provide fuse recommendations in our datasheet based on load current and type. The relay itself does not have overcurrent protection, so proper fusing is essential to prevent damage. Our FAQ section includes guidelines on fuse selection. For specialized protection, we offer variants with integrated over-temperature protection that automatically shuts off the output if overheating occurs. Always ensure that the load current does not exceed the relay's rating and that the supply voltage is within specifications.

Related article

Solid State Relay vs. Electromechanical Relay — The Ultimate Buyer's Guide for Industrial Automation

16

Jun

Solid State Relay vs. Electromechanical Relay — The Ultimate Buyer's Guide for Industrial Automation

View More
What types of sensors are compatible with a standard temperature controller?

13

Jul

What types of sensors are compatible with a standard temperature controller?

Thermocouples: The workhorse of high-temperature sensing Walk into almost any industrial plant and you will find thermocouples scattered across furnaces, ovens, kilns, and exhaust streams. They are cheap, tough, and handle temperatures that would mel...
View More
What industries benefit most from using a PID temperature controller?

27

Jul

What industries benefit most from using a PID temperature controller?

More Than a Component—A Critical Enabler Walk through almost any modern production facility, and the chances of spotting a PID temperature controller on a panel are remarkably high. These devices have become so embedded in industrial infrastruc...
View More
How to calibrate a temperature controller to ensure accurate readings?

03

Aug

How to calibrate a temperature controller to ensure accurate readings?

The Hidden Cost of an Uncalibrated Controller Temperature controllers are the silent workhorses of industrial production. When they drift, the consequences are rarely immediate—which makes them dangerous. A controller reading 2°C low in a h...
View More

Reviews

John Miller

We integrated the Solid State Relay 40A into our temperature control units for industrial ovens. The relay has demonstrated outstanding reliability with zero failures after 6 months of continuous operation. The zero-crossing switching significantly reduced our EMI issues, and the thermal management design keeps the relay cool even at full load. Installation was straightforward with the included mounting hardware. The product documentation and technical support from Suosite were excellent. We've standardized on this relay for all our new designs.

Maria González

As an OEM supplier, we required a solid state relay that could be customized to fit our specific voltage and control requirements. Suosite provided exceptional support, adjusting the input logic and terminal layout to match our PCB design. The relay's performance has been flawless, and its compact size allowed us to reduce the size of our control panel. The CE certification gave us confidence in shipping to European markets. We highly recommend the Solid State Relay 40A for its quality, flexibility, and competitive pricing.

Get a Free Quote

Our representative will contact you soon.
Email
Name
Company Name
Message
0/1000
solid state relay 10a solid state relay 25a solid state relay 40a solid state relay 20a solid state relay 30a solid state relay 50a solid state relay 60a solid state relay 80a
Integrated Over-Temperature Protection

Integrated Over-Temperature Protection

Our Solid State Relay 40A features an optional built-in thermal sensor that continuously monitors the internal temperature. If the junction temperature exceeds a safe threshold, the relay automatically shuts off the output, preventing permanent damage and ensuring safe operation. This feature is invaluable in applications where cooling may be compromised or ambient temperatures vary unexpectedly. It eliminates the need for external thermal protection circuits, saving space and cost. The protection circuit has a high repeatability and fast response, enhancing system safety and reliability. This sets our relay apart from standard SSRs, offering you peace of mind and reducing maintenance costs.
High dv/dt Immunity and Noise Suppression

High dv/dt Immunity and Noise Suppression

With advanced semiconductor technology and optimized snubber circuits, our 40A SSR offers superior immunity to voltage spikes and rapid voltage changes, maintaining stable operation in noisy industrial environments. This reduces the risk of false triggering and ensures clean switching, protecting both the relay and connected loads. The low EMI emission meets EN61000-6-4 standards, making it suitable for sensitive electronic equipment. This feature is particularly beneficial in applications like variable frequency drives or power supplies where switching noise can disrupt other components. By choosing our relay, you minimize interference and improve overall system performance.
Wide Operating Temperature Range and Derating Flexibility

Wide Operating Temperature Range and Derating Flexibility

Designed to operate in extreme conditions, the Solid State Relay 40A functions reliably in ambient temperatures from -30°C to 80°C, with proper derating at higher currents. This wide range ensures consistent operation in both cold and hot climates, making it suitable for outdoor equipment or unheated facilities. Our relay's thermal design incorporates larger thermal pads and high-conductivity substrates, improving heat transfer. The derating curve is linear and predictable, allowing engineers to optimize performance for their specific environment. This flexibility enables you to use the same relay model in multiple applications, simplifying inventory and reducing costs. With Suosite, you get a relay that adapts to your needs, not the other way around.
Newsletter
Please Leave A Message With Us
Zhejiang Suosite Electrical Technology Co., Ltd.

Copyright © 2026 by Zhejiang Suosite Electrical Technology Co., Ltd. - Privacy policy