LED
LCD
SSR-40DA Solid State Relay SSR-40DA (3-32Vdc / 24-380VAc)
Product Overview
The SSR-40DA from Pro Tronix is the higher-capacity sibling of the 25DA, designed for demanding applications that require switching currents up to 40A. Because it is a “Solid State” device, it eliminates the mechanical wear, arcing, and acoustic noise associated with traditional magnetic contactors.
It is perfectly suited for PID control systems where the relay must cycle on and off rapidly to maintain a precise temperature. With a wide input range of 3V to 32V DC, it is fully compatible with microcontrollers like Arduino, as well as industrial PLCs and temperature controllers.
Technical Specifications
| Feature | Specification |
| Model | SSR-40DA |
| Control Input Voltage | 3V – 32V DC |
| Load Output Voltage | 24V – 380V AC |
| Rated Load Current | 40A |
| Switching Type | Zero Cross Trigger |
| Insulation Resistance | 1000MΩ / 500V DC |
| Ambient Temperature | -30°C to +75°C |
| Indicator | Built-in Red LED |
| Supplier | Pro Tronix |
Key Features
High Load Capacity: Rated for 40A, making it ideal for large industrial heaters, kilns, and high-wattage AC motors.
Spark-Free Switching: Ideal for environments where explosive gases or sensitive electronics are present, as there is no physical contact arcing.
Opto-Isolation: Protects your low-voltage control circuit (Arduino/PLC) from the high-voltage AC load.
Rapid Response: Features ultra-fast switching speeds (≤10ms), enabling precise Pulse Width Modulation (PWM) for thermal stability.
Common Applications
High-Power 3D Printers: Controlling AC-powered heated beds for large-format industrial 3D printers.
Industrial Heating: Powering heating elements in plastic extrusion machines, ovens, and injection molding equipment.
Large Scale Automation: Toggling heavy AC loads in smart building systems or automated factory lines.
Commercial Appliances: Used in professional coffee machines, pizza ovens, and laboratory equipment.
⚠️ Maintenance Tip: For any load exceeding 10A, a dedicated aluminum heat sink is required. For the full 40A capacity, active cooling (a fan) is highly recommended to prevent thermal shutdown.
You can see the rest of our available relays from here: Relay | Pro Tronix
