The ST31 three-phase rectifier thyristor trigger board is built around a 32-bit industrial-grade high-performance microprocessor, designed to meet highly digitized safety standards. It supports both network remote control and on-site control, with open Fuzzy-PID parameter adjustment. The board integrates three regulation modes—open-loop voltage regulation, closed-loop constant voltage, and constant current—enabling thyristor control for constant voltage with current limiting or constant current with voltage limiting.

Fault alarms and interface parameters are displayed via an LCD screen or touchscreen with a Chinese menu. Set parameters are automatically stored. The control board includes functions such as phase-loss protection, soft start on power-up, soft shutdown, constant current output, constant voltage output, overvoltage protection, overcurrent protection, short-circuit protection, and operational status indication.

It supports three-phase fully controlled bridge rectification, double inverse star rectification, and anti-parallel thyristor AC triggering methods. It can trigger thyristors rated up to 3000A and is suitable for a wide range of industrial applications involving voltage and current regulation, including resistive, inductive, capacitive, and transformer primary side loads. It is widely used in equipment such as electrolysis, electroplating systems, battery charging/discharging, three-phase thyristor power supplies, electric heating temperature control, and arc discharge control systems.

Note: The ST31 model is no longer supplied to new customers. For requirements, please select the ST33 model, which offers identical performance.

Technical Specifications:

Power Supply: 220/380Vac ±15%, 50/60Hz

Main Circuit Operating Voltage: 50–660Vac ±15%, 50/60Hz

Voltage Adjustment Range: 0 to full-scale voltage

Current Adjustment Range: 0 to full-scale current

Display Method: LCD screen with Chinese interface

Phase Shift Range: 0–178°

Adjustment Output Resolution: 1/4000

Stability Accuracy: Better than ±1%

Trigger Current: ≥ 750mA

Trigger Capacity: ≤ 3000A unidirectional thyristor

PID Dynamic Response Time: ≤ 50ms

Overshoot: ≤ 10%

Input Signals: DC 0-5V, DC 0-10V, 0-10mA, 4-20mA, 10K potentiometer adjustment

Three-Phase Trigger Imbalance: ≤ 0.3°

Suitable Loads: Resistive, inductive, capacitive, transformer primary side, and other loads

Alarm Relay Contact Rating: 250Vac / 10A

Dielectric Strength: 3500 VRMS

Dimensions: 240 × 160 × 50 mm

Panel Cutout Dimensions: 225 × 145 mm

Weight: 1 kg

Operating Environmental Conditions:

Ambient Temperature: -20°C to 60°C

Relative Humidity: ≤ 90% RH (non-condensing)

Indoor Installation: Environment free from flammable, explosive, corrosive gases, and conductive dust; vibration less than 0.5G.

Altitude: Below 3000 meters. For altitudes exceeding 3000 meters, appropriate derating should be applied.

Product Compliance Standards:

IEC 60947-4-2: Low-voltage switchgear and controlgear – Part 4-2: Contactors and motor-starters – AC semiconductor motor controllers and starters.

GB 14048.6-1998: Low-voltage switchgear and controlgear – Part 4-2: Contactors and motor-starters – AC semiconductor motor controllers and starters.

GB 3797-89: Electrical control equipment – Part 2: Electrical control equipment with electronic components.

IEC 61000-4: Electromagnetic compatibility (EMC) – Testing and measurement techniques.

IEC 65: Safety requirements for mains-powered electronic and related equipment for household and similar general use.