Solid state relays (SSRs) are essential components for modern electrical control systems, offering silent operation, long lifespan, and faster switching speeds than mechanical relays. Choosing the correct SSR ensures reliable performance, prevents premature failure, and maintains the safety of your electrical circuits. This guide will help you navigate the key factors to consider when purchasing the best solid state relay for your needs.
- ♥【What You Get】Each package With 2 mini bag of thermal grease which apply on the back of the SSR to make the temperature dissipate faster.
- ♥ Product Name: solid state module relay SSR-25DA, 3-32VDC/24-480VAC ; Current & Frequency:25A,50/60Hz.
- ♥ Total size (approximate):58 x 45 x 32mm/2.3" x 1.8" x 1.26" (l*w*t); Net weight:116g; Material:metal, plastic, electronic parts.
- ♥ SSR Application: with a switch no spark, no noise,high switching speed,anti-corrosion,moisture-proof,anti-vibration,long life.high reliability,electromagnetic compatibility and other characteristics.
- ♥ Solid state relay ideal for automatic process control application, a must component for temperature controller and other machinery control system.
- 𝗢𝗣𝗧𝗜𝗠𝗜𝗭𝗘𝗗 𝗣𝗘𝗥𝗙𝗢𝗥𝗠𝗔𝗡𝗖𝗘: Each BlueStars SSR-25DD Solid State Relay comes with detailed instructions for optimal installation, ensuring faster temperature dissipation and extended lifespan.
- 𝗣𝗥𝗘𝗖𝗜𝗦𝗘 𝗦𝗣𝗘𝗖𝗜𝗙𝗜𝗖𝗔𝗧𝗜𝗢𝗡𝗦: BlueStars Solid State Relay SSR-25DD, DC 3-32V Input, DC 5-200V Output, 25A Current & Frequency: 50/60Hz. Total size (approximate): 58 x 45 x 32mm; Net weight: 168g...
- 𝗩𝗘𝗥𝗦𝗔𝗧𝗜𝗟𝗘 𝗔𝗣𝗣𝗟𝗜𝗖𝗔𝗧𝗜𝗢𝗡: Experience a switch with no spark, no noise, high switching speed, anti-corrosion, moisture-proof, anti-vibration, long life, high reliability, and electromagnetic...
- 𝗥𝗢𝗕𝗨𝗦𝗧 & 𝗥𝗘𝗟𝗜𝗔𝗕𝗟𝗘: Crafted with a heat-dissipating metal back plate and copper terminal lug for superior conductivity. BlueStars ensures longevity with a high-quality semiconductor optocoupler, spark-proof...
- 𝗟𝗜𝗙𝗘𝗧𝗜𝗠𝗘 𝗔𝗦𝗦𝗨𝗥𝗔𝗡𝗖𝗘: Enjoy reliable performance and peace of mind with BlueStars lifetime protection, covering any defects or issues that may arise. Your satisfaction is our priority.
- ♥【What You Get】Each package With 2 mini bag of thermal grease which apply on the back of the SSR to make the temperature dissipate faster.
- ♥ Product Name: solid state module relay SSR-25DD, 3-32VDC/5-220VDC ; Current & Frequency:25A,50/60Hz.
- ♥ Total size (approximate):58 x 45 x 32mm/2.3" x 1.8" x 1.26" (l*w*t); Net weight:116g; Material:metal, plastic, electronic parts.
- ♥ SSR Application: with a switch no spark, no noise,high switching speed,anti-corrosion,moisture-proof,anti-vibration,long life.high reliability,electromagnetic compatibility and other characteristics.
- ♥ Solid state relay ideal for automatic process control application, a must component for temperature controller and other machinery control system.
- Input:3-32Vdc,Output:5-60Vdc
- Without a heatsink installed, the maximum current is 1A.
- Long lifespan: uses optocoupler isolation and is contactless, so there's no mechanical lifespan limit.
- Fast response,high trigger,no noise.
- Commonly used for development boards like ESP32 and Raspberry Pi.
- 【Model】SSR-40DA 40A 250V Solid State Relay Module, for PID thermostat temperature controller
- 【SSR-40DA Parameter】Solid state module relay SSR-40DA, 3-32VDC/24-380VAC, control mode: DC to AC
- 【Relay Size】(L*W*H)62×45×24mm/2.48 x 1.73 x 0.94"
- 【SSR Application】No electric spark, no noise, high switching speed, especially suitable for corrosion, moisture, dust resistant and other harsh environments. Widely used in many automatic control systems
- 【Package Included】3pcs SSR-40DA solid state relay module
- ♥【What You Get】Each package With 2 mini bag of thermal grease which apply on the back of the SSR to make the temperature dissipate faster.
- ♥ Product Name: solid state module relay SSR-40DA, 3-32VDC/24-480VAC ; Current & Frequency:40A,50/60Hz.
- ♥ Total size (approximate):58 x 45 x 32mm/2.3" x 1.8" x 1.26" (l*w*t); Net weight:116g; Material:metal, plastic, electronic parts.
- ♥ SSR Application: with a switch no spark, no noise,high switching speed,anti-corrosion,moisture-proof,anti-vibration,long life.high reliability,electromagnetic compatibility and other characteristics.
- ♥ Solid state relay ideal for automatic process control application, a must component for temperature controller and other machinery control system.
- ♥【What You Get】Each package With 2 mini bag of thermal grease which apply on the back of the SSR to make the temperature dissipate faster.
- ♥ Product Name: solid state module relay SSR-25DA, 3-32VDC/24-480VAC ; Current & Frequency:25A,50/60Hz.
- ♥ Total size (approximate):58 x 45 x 32mm/2.3" x 1.8" x 1.26" (l*w*t); Net weight:116g; Material:metal, plastic, electronic parts.
- ♥ SSR Application: with a switch no spark, no noise,high switching speed,anti-corrosion,moisture-proof,anti-vibration,long life.high reliability,electromagnetic compatibility and other characteristics.
- ♥ Solid state relay ideal for automatic process control application, a must component for temperature controller and other machinery control system.
- ♥【What You Get】Each package With 2 mini bag of thermal grease which apply on the back of the SSR to make the temperature dissipate faster.
- ♥ Product Name: solid state module relay SSR-40AA, 70-250VAC/24-480VAC ; Current & Frequency:25A,50/60Hz.
- ♥ Total size (approximate):58 x 45 x 32mm/2.3" x 1.8" x 1.26" (l*w*t); Net weight:116g; Material:metal, plastic, electronic parts.
- ♥ SSR Application: with a switch no spark, no noise,high switching speed,anti-corrosion,moisture-proof,anti-vibration,long life.high reliability,electromagnetic compatibility and other characteristics.
- ♥ Solid state relay ideal for automatic process control application, a must component for temperature controller and other machinery control system.
- Solid State Relay Module Board has been assembled, and electrical test passed
- Led indicator for each relay
- Size: 155 x 55 x 24 mm (approximately 6.1 x 2.17 x 0.95 inch)
- Has been assembled, and electrical test passed. Led indicator for each relay. Size: 155 x 55 x 24 mm (approximately 6.1 x 2.17 x 0.95 inch) Input control signal voltage: 0V - 0.5V Low stage (SSR is OFF), 0.5V - 2.5V (unknown state), 2.5V - 20V High state...
- Load voltage range: 75 to 264VAC (50/60Hz); Load current: 0.1 to 2 AMP Standard interface that can be controlled directly by microcontroller (Compatible with Arduino , 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic)
- Combined total continuous current rating of 140 amps
- Single wire activation by switching power or ground
- Available in Red or Black
- Channels can be run in parallel for devices requiring more than 35 Amp single-channel rating
- Operates from 7-Volts to 20-Volt supply
- 4 Independent Channels, 35 Amps each continuous or 100 Amps for 8 seconds
- Over-temp, short circuit and overload protection
- Multiple mounting options
- A PWM signal can be used in the Solid-State Relay Module with a maximum frequency of 150 hertz and a duty cycle range from 50% to 90%.
- Diagnostic LED’s and status indicators
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Last update on 2026-07-18 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Solid State Relays
Understanding SSR Types
- DC-DC Relays: Used for switching DC loads with a DC control signal. Common in battery-powered systems and DC motor control.
- AC-DC Relays: Control AC loads using a DC control signal. Widely used in automation, lighting control, and appliance switching.
- AC-AC Relays: Switch AC loads with an AC control signal. Suitable for industrial machinery, HVAC systems, and general AC power control.
Key Specifications to Consider
- Voltage Rating: The SSR must be rated to handle the maximum voltage of the load circuit. Ensure a safety margin, especially for inductive loads.
- Current Rating: Select an SSR with a continuous current rating exceeding the load's operating current by at least 25-50% to prevent overheating. Consider peak or inrush current for certain loads (e.g., motors).
- Control Voltage: Match the control voltage input range of the SSR to your control signal source (e.g., 3-32V DC, 90-280V AC).
- Switching Method: Zero-crossing (for resistive loads, minimizes RFI) or random/instantaneous turn-on (for inductive loads, prevents voltage spikes).
- Heat Dissipation: High-current SSRs often require heatsinks to operate effectively and prevent thermal shutdown. Check the SSR's thermal resistance and derating curves.
Mounting and Environmental Factors
- Consider the mounting method required (panel mount, DIN rail mount, PCB mount).
- Assess the operating environment. Look for SSRs with appropriate IP ratings if dust or moisture is a concern. Ensure the ambient temperature is within the SSR's specified operating range.