STVP-936 LCD Adjustable Voltage Protector User Manual

1. Product Overview

The Walfront STVP-936 is a sophisticated three-phase four-wire automatic reset over-voltage, under-voltage, and multi-function protector. Designed for power systems and electrical equipment, it provides comprehensive protection against various electrical anomalies, ensuring the safety and longevity of connected devices. It integrates over-voltage, under-voltage, over-current, three-phase voltage unbalance, phase sequence (phase dislocation), and phase-break protection into a single unit.

Figure 1: Front view of the STVP-936 LCD Adjustable Voltage Protector, showing the LCD display and control buttons.

Key Features:

• Automatic Reset: Automatically restores power when voltage returns to normal after an anomaly.
• Multifunctional Protection: Combines over-voltage, under-voltage, over-current, three-phase unbalance, phase sequence, and phase-break protection.
• LCD Screen: Clear display for real-time voltage and current readings, and easy parameter adjustment.
• Fault Inquiry: Allows users to check fault history.
• Adjustable Parameters: Customizable protection values and recovery times.

2. Setup and Installation

2.1 Safety Precautions

• Ensure all power is disconnected before installation or maintenance.
• Installation should be performed by a qualified electrician.
• Verify correct wiring according to the provided diagrams and local electrical codes.
• Do not operate the device if it appears damaged.

2.2 Mounting Instructions

The STVP-936 is designed for rail vertical installation. Ensure adequate space for ventilation and wiring connections. Mount the device securely on a standard DIN rail within an electrical enclosure.

Figure 2: Dimensions of the STVP-936, indicating its compact size for rail mounting.

2.3 Wiring Diagram

The device is suitable for three-phase four-wire power systems (230V/400VAC 50/60Hz). Connect the incoming power lines (L1, L2, L3, N) to the "IN" terminals and the outgoing load lines to the "OUT" terminals. Refer to the diagram printed on the device for specific terminal identification (N, L1, L2, L3).

Figure 3: Side view illustrating the input (IN) and output (OUT) terminals for wiring connections.

3. Operation Guide

3.1 LCD Display

The LCD screen provides real-time monitoring of voltage and current. It also displays fault codes and allows for parameter configuration.

Figure 4: Detailed view of the LCD display and the 'SET', 'Up', and 'Down' buttons for navigation and adjustment.

3.2 Setting Parameters

Use the SET button to enter the parameter setting mode. Use the Up (▲) and Down (▼) buttons to adjust values. Press SET again to confirm and move to the next parameter. The device will automatically save settings after a short period of inactivity in setting mode.

Adjustable Parameters:

• Current Rating: 1-63A adjustable (default 63A).
• Overvoltage Protection Value (Uvo): 221V-300V-OFF (default 280V).
• Overvoltage Recovery Value: 220V-299V (default 250V).
• Overvoltage Protection Action Time: 0.1-10 seconds (default 0.2 seconds).
• Undervoltage Protection Value (Uve): 219V-150V-OFF (default 160V).
• Undervoltage Recovery Value: 220V-151V (default 180V).
• Undervoltage Protection Action Time: 0.1-10 seconds (default 0.2 seconds).
• Overcurrent Protection Action Time: 1-512 seconds (default 5 seconds).
• Three-Phase Voltage Unbalance Protection Value: 5%-90%-OFF (default 25%).
• Phase Voltage Unbalance Protection Action Time: 0.1-10 seconds (default 2.0 seconds).
• Power-On Delay Time: 2-255 seconds (default 2 seconds).
• Failure Recovery Delay Time: 2-512 seconds (default 60 seconds).

3.3 Restoring Factory Settings

The device has a function to restore factory default settings. Refer to the specific instructions in the full product manual or contact support for the exact procedure.

4. Maintenance

The STVP-936 is designed for minimal maintenance. However, periodic checks are recommended to ensure optimal performance and safety:

• Cleaning: Keep the device clean and free from dust. Use a dry, soft cloth for cleaning. Do not use liquid cleaners.
• Connection Check: Periodically inspect wiring connections to ensure they are secure and free from corrosion.
• Environmental Conditions: Ensure the operating environment remains within specified temperature and humidity ranges.

5. Troubleshooting

If the device is not functioning as expected, consider the following common issues:

• No Power/Display Off: Check incoming power supply and wiring connections. Ensure the device is correctly installed.
• Frequent Tripping: Review the set protection parameters (overvoltage, undervoltage, overcurrent) to ensure they are appropriate for your electrical system. Check for actual power fluctuations or overloads.
• Incorrect Readings: Verify wiring. If readings are consistently inaccurate, the device may require professional inspection.
• Device Not Resetting: Check the failure recovery delay time setting. Ensure the fault condition has cleared.

The device also features a fault inquiry function. Consult the full product manual for details on how to access and interpret fault codes.

6. Technical Specifications

7. Warranty and Support

7.1 Warranty Information

Please refer to the manufacturer's official warranty policy for details regarding coverage, terms, and conditions. Typically, electronic devices come with a limited warranty against manufacturing defects.

7.2 Customer Support

For technical assistance, troubleshooting, or warranty claims, please contact Walfront customer support. You can find more information and contact details by visiting the official Walfront store page:

Visit the Walfront Store on Amazon