1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the SINOTIMER ST17VA Square LED Digital Voltmeter Ammeter Signal Light. This device is designed to measure AC voltage and current, displaying the values on a clear LED screen. It is suitable for various electrical applications requiring real-time monitoring of electrical parameters.
The ST17VA model is a square-shaped signal digital display lamp, combining voltmeter and ammeter functions.
2. Safety Information
WARNING: Electrical shock hazard. Installation and servicing should only be performed by qualified personnel.
- Always disconnect power before installing or servicing the device.
- Ensure all connections are secure and properly insulated.
- Do not operate the device outside its specified voltage and current ranges.
- Keep the device away from moisture and extreme temperatures.
- Verify the correct wiring of the current transformer (CT) to avoid damage to the meter or inaccurate readings.
3. Product Overview
The SINOTIMER ST17VA is a compact, square-shaped LED digital display unit that simultaneously shows AC voltage and current. It comes with a separate current transformer (CT) for current measurement.
3.1 Components
- Square LED Digital Voltmeter Ammeter Signal Light (available in Red, White, Blue, Green, Yellow)
- Current Transformer (CT)
- Connecting wires
3.2 Visual Overview
4. Specifications
| Feature | Specification |
|---|---|
| Model Number | ST17VA |
| Brand Name | SINOTIMER |
| Display Type | Digital Only |
| Display | Voltage & Current |
| Power Supply | AC |
| Power Source | AC |
| Voltage Range | AC 60-500V |
| Measuring Range (Current) | 1-100A |
| Accuracy Class | Class A |
| Install Size | 22mm |
| Dimensions (D*H) | 2.88*5cm / 1.10"*1.97" |
| Shape | Square |
| Operating Temperature | -25℃ ~ +65℃ |
| Relative Humidity | ≤ 98% |
| Allowable Voltage Fluctuation | ±20% |
| Continuous Operating Life | ≥ 30000H |
| Brightness | ≥ 100cd/m² |
| Protection Degree (Head) | IP65 (IP67 available on request) |
| Applying Frequency | AC50~60Hz |
| Insulation Resistance | ≥ 2MΩ |
| Power Frequency Withstand Voltage | 2.5KV/1min (effective AC value) |
| Pollution Degree | 3, Installation Group III |
| Battery Included | No |
| Data Record | No |
5. Setup and Installation
The ST17VA meter is designed for a 22mm installation hole. Ensure the mounting surface is clean and dry before installation.
5.1 Wiring Instructions
The meter requires two main connections: one for voltage measurement and one for current measurement via the current transformer (CT).
- Voltage Connection: Connect the two main wires from the meter (typically red and black, or as indicated on the device) directly to the AC circuit where you want to measure voltage. These wires provide power to the meter and measure the voltage.
- Current Transformer (CT) Connection: The current transformer (CT) is a separate ring-shaped component. The main load wire (the wire carrying the current you wish to measure) must pass through the center hole of the CT. The two small wires from the CT then connect to the dedicated current input terminals on the meter.
Note: The CT is included with the meter. Ensure the load wire passes through the CT correctly. The CT wires are typically connected to a small connector that plugs into the back of the meter.
6. Operating Instructions
Once properly installed and powered, the ST17VA meter will automatically display the measured AC voltage and current on its LED screen.
- Voltage Display: The upper part of the display shows the AC voltage in Volts (V).
- Current Display: The lower part of the display shows the AC current in Amperes (A).
6.1 Operating Environment
The device is designed to operate reliably under the following conditions:
- Ambient Temperature: -25℃ to +55℃
- Relative Humidity: ≤ 98%
- Vibration Frequency: Normally workable when vibration frequency is 2-80Hz with acceleration of 0.7g.
- Pollution Degree: 3, Installation Group III.
- Devices marked with "TH" can operate in damp-heat environments.
7. Maintenance
- Keep the display clean and free from dust. Use a soft, dry cloth for cleaning.
- Regularly check all wiring connections for tightness and signs of wear or damage.
- Ensure the operating environment remains within the specified temperature and humidity ranges.
- Do not attempt to open or repair the device yourself. Refer to qualified service personnel.
8. Troubleshooting
- No Display: Check power connections to the meter. Ensure the AC voltage is within the 60-500V range.
- Current Not Displaying (or showing 0.0A):
- Ensure the load wire is correctly passed through the current transformer (CT).
- Verify the CT's small wires are securely connected to the meter.
- The meter will not display current values below 1A. If your load is less than 1A, the display will show 0.0A. - Inaccurate Readings:
- Check all wiring for proper connection and integrity.
- Ensure the meter is operating within its specified environmental conditions. - Current Indicator Corrupt: If the voltage is displayed but the current indicator is faulty, check the CT connections and the CT itself. If the issue persists, the unit may require replacement.
9. User Tips
- This meter is designed for AC power only and is not suitable for DC applications (e.g., automotive).
- For multi-phase systems, these meters can be very convenient for monitoring and balancing loads across phases.
- The current transformer (CT) cable can potentially be extended if needed, but ensure the extension uses appropriate gauge wire and maintains signal integrity to avoid measurement inaccuracies.
10. Warranty and Support
For detailed warranty information, technical support, or to view the original user manual in PDF format, please refer to the official documentation provided by the seller. A PDF user manual is available at: User manual (PDF).