SF250 High-Frequency Induction Preheater Control Board serves as the essential control power supply for preheating equipment prior to high-standard metal rubber coating. It is suitable for online preheating in the wire and cable industry, effectively removing impurities from the metal surface and ensuring the metal and rubber blend into one by maintaining consistent temperature between the metal and rubber. This eliminates defects such as metal exposure after rubber coating. It also maintains constant temperature while adjusting the preheating voltage in response to changes in line speed.

Input Voltage: AC380 three-phase full-wave rectification, with a DC bus voltage of approximately 560V

Output Current: Alternating square wave, 0A–100A. Constant voltage, constant temperature, or constant current modes can be freely set as preferred.

Output Frequency: 20 kHz–50 kHz, fixed frequency. Utilizes Infineon high-frequency IGBTs with phase-shift inversion modulation and duty cycle control for constant current voltage regulation.

Output Voltage/Current Accuracy: 0.5%

Communication Protocol: MODBUS RTU, 485 half-duplex two-wire

Power Module: Compatible with both MOSFETs and IGBTs

Minimum Dead Time for Upper/Lower Bridge Arms: Lower limit dead time greater than 3 microseconds, ensured by constraining the maximum frequency

Duty Cycle: Adjustable from 5% to 48% in combination with frequency

Communication Functions: Read real-time voltage and current values (for Joule heat calculation, requiring true RMS values) as well as operational status (duty cycle, bus voltage, frequency, temperature, apparent power)

Main Circuit Configuration: H-bridge with symmetrical positive and negative half-cycles. Half-bridge configurations are also possible, with attention to magnetic bias protection.