Using SCR trigger to realize stepless speed regulation. Introduce voltage negative feedback technology to make the speed more stable. with current protection cut-off device to make the performance more reliable. cooperate with displacement to realize automatic stepless speed regulation. cooperate with p oelectric switch to realize remote control. with soft start device to the motor starting current is too large. Use environment: 1. Ambient air temperature:-10-40℃; 2. the air relative humidity below 85%, well ventilated; 3. no dangerous medium and no conductive metal powder. Product introduction: This product has the advantages of small size, convenient installation, high speed regulation accuracy, low price and complete functions. Widely used in bag-making machine, -cutting machine, wire drawing, extrusion machinery, food production, printing and packaging and other industries, and can be used with permanent magnet, separately excited and parallel excited DC motors.Power is supplied to the armature of small DC motor to realize constant torque stepless speed regulation of DC motor. The main circuit of this device adopts single-phase bridge semi-control circuit, with voltage negative feedback, current cut-off feedback circuit and soft start, etc.,to improve the speed regulation accuracy and limit the starting current. The control circuit is triggered by single-junction transistor, which has simple circuit, stable and reliable operation and stable temperature compensation performance. External controls include: displacement controller, NPN or PNP p oelectric switch. Connection mode: terminal type. Input voltage:AC220v 10%,50/60Hz Output current:3.5A Static accuracy:5% Adaptive motor power:50-500W Armature output voltage:DC0-220V Excitation output voltage:DC200V/1A Overall dimensions:146x100x40mm Color:As Shown Material:PCB Package Contents: 1set * 500W SCR-08 DC motor speed control board(The color of accessories is random,and the designation is not accepted) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.