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 photoelectric switch to realize remote control. with soft start device to eliminate 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 explosive 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, cross-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 photoelectric 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