SCR Power Regulator User Manual

1. Product Overview

The SCR power regulator is an automatic silicon-controlled rectifier (SCR) device designed for high-voltage power regulation. It uses thyristor technology to control AC voltage and power supplied to resistive or inductive loads. The product is widely used in electric furnaces, ovens, chemical heating systems, and industrial plastic machinery for power and temperature regulation.

Main features:

• Suitable for single-phase or three-phase AC power up to 380 V or higher.

• Uses SCR phase-control or zero-cross modulation for precise power regulation.

• Open-loop control with input signal options such as potentiometer, 0–10 V, or 4–20 mA.

• Optional forced air or water cooling for high current models.

• Compact design for control cabinet installation.

2. Model and Technical Specifications

Typical specifications (may vary per model):

3. Safety Instructions

⚠ Important: Read and follow all safety instructions before installation or operation.

• Only qualified electrical technicians should handle installation and maintenance.

• Ensure power is completely disconnected before wiring.

• Never exceed the rated voltage or current printed on the product nameplate.

• Use proper short-circuit and overload protection devices.

• Always ground the housing and heat sink properly.

• Avoid operating in environments with high humidity, conductive dust, or corrosive gas.

• Gradually increase power during initial setup to prevent overload or surge effects.

4. Structure and Terminal Description

Refer to your actual product’s terminal markings. The following layout is typical:

Main Power Terminals:

• Single-phase: L, N (input); U, V (output)

• Three-phase: R, S, T (input); U, V, W (output)

Control Terminals:

• Potentiometer: +10 V / WIPER / GND

• Analog signal: IN+, IN– (for 0–10 V or 4–20 mA input)

• Enable/Start: EN or ON/OFF terminals (if available)

Indicators:

• Power LED: Controller is powered

• Output LED: SCR firing active

• Alarm LED / Code: Displays faults such as overcurrent or overtemperature

5. Installation Guidelines

• Ambient conditions:

• Temperature: –10 °C to +40 °C

• Humidity: ≤ 90%, non-condensing

• No corrosive gas or strong vibration

• Mounting:

• Install vertically on a metal panel within a control cabinet.

• Maintain clearance of ≥100 mm above/below and ≥50 mm at the sides.

• Cooling:

• Ensure unrestricted airflow through the heat sink.

• Use forced ventilation for models above 100 A.

• Grounding:

• Connect the PE terminal firmly to industrial ground.

6. Wiring Instructions

Before wiring: Disconnect all power sources and verify wiring matches rated voltage.

6.1 Main Circuit Wiring

• Single-phase load:
  Connect input L to terminal L (or L1), output U to the load, and return to N (or the second phase).
  Add a fuse or circuit breaker in series for protection.

• Three-phase load:
  Connect supply lines R, S, T to the input side, and outputs U, V, W to the load terminals.
  Use appropriate wiring diagrams for star or delta load connections.

6.2 Control Circuit Wiring

1. Potentiometer control:
   +10 V → potentiometer end A
   GND → potentiometer end B
   WIPER → control signal IN
   Rotating clockwise increases output voltage.

2. Analog signal control:
   IN+ and IN– connect to the control source (0–10 V or 4–20 mA).
   Use shielded cables and keep signal wires away from power lines.

3. Enable switch (if available):
   Connect a relay or switch contact between EN and GND for remote enable/disable.

7. Operation and Usage

1. Pre-check:

• Verify all terminals are tightened and within rated limits.

• Ensure protective devices are properly installed.

2. No-load test:

• Power on without load or with a small test load.

• Adjust potentiometer slowly to verify proportional voltage change.

3. Full-load operation:

• Connect actual load after successful no-load test.

• Gradually increase control signal and observe current and temperature.

• Do not exceed continuous rated current.

4. Recommendations:

• Avoid rapid signal changes.

• Regularly recheck connections to prevent overheating from loose terminals.

8. Protection and Troubleshooting

Built-in protection features (if supported):

• Overcurrent protection

• Phase-loss detection (three-phase models)

• Overtemperature shutdown

• Load open detection

Common faults and remedies:

9. Maintenance

To maintain reliable operation:

• Every 3–6 months:

• Disconnect power and retighten all terminals.

• Clean dust from heat sink and cooling fans.

• Every 12 months:

• Inspect for discoloration or damage.

• For heavy-duty use, consider adding extra cooling measures.

Do not replace internal components unless authorized by the manufacturer. For repair or calibration, contact the supplier or an approved service center.