1. Introduction
The RuoShui 4090 series desktop LCR meter is a high-precision instrument designed for measuring capacitance, resistance, impedance, and inductance. It features a 3.5-inch TFT display, a user-friendly interface, and a variety of measurement parameters. This device is ideal for laboratories, factories, radio hobbyists, and educational settings, offering remote control capabilities via USB and RS232, as well as component sorting functions. With a basic accuracy of 0.2%, it provides reliable and precise measurements for various electronic components.
Figure 1: RuoShui Benchtop Digital LCR Meter with key features.
2. Key Features
- Measurement frequency up to 100kHz.
- Adjustable test level from 100mV to 2000mV.
- Supports measurement of DC resistance and electrolytic capacitors.
- Internal bias voltage output (1mV-1500mV).
- Automatic identification of component types for measurement.
- 3.5-inch TFT display with 5 and a half digits resolution.
- USB and RS232 communication interfaces for remote control.
- Handler interface for component sorting.
- Data recording function (maximum, minimum, and average values).
- Supports SCPI communication protocol.
- Customizable system settings including language, buzzer, and screen brightness.
- Basic accuracy of 0.2%.
- Manual and automatic ranging.
- Open circuit and short circuit correction functions.
- Comparator with sorting and alarm functions.
- Multiple test ports for versatile connections.
3. Package Contents
Upon unpacking, please verify that all items listed below are present and in good condition:
- Digital LCR Meter (Main Unit)
- Three-core Power Cord
- Four-terminal Pair Kelvin Test Cable
- Product Manual
- Fuse
Figure 2: Included packaging accessories.
4. Product Overview
4.1. Front Panel
Figure 3: Front Panel Layout.
- 3.5-inch TFT Display: Shows measurement results and settings.
- Switch Key: Used for navigating menus and changing settings.
- Arrow Keys: For navigation and value adjustment.
- Basic Measurement Function Keys: Buttons for various measurement modes (e.g., AUTO, COMPARE, SAVE, TOL%, HOLD, DCR, MAX, MIN, AVG).
- Power Switch Key: Turns the device on/off.
- Ground Port: For grounding the instrument.
- Test Clip Jacks: Connectors for Kelvin test cables.
4.2. Rear Panel
Figure 4: Rear Panel Layout.
- HANDLER Interface: For connecting to external sorting devices.
- RS-232 Interface: For serial communication with a computer.
- USB Interface: For USB communication and software upgrades.
- Voltage Jack: Power input connector.
- Voltage Selection Switch: To select between 110V and 220V power input.
4.3. Dimensions
Figure 5: Device Dimensions.
The approximate dimensions of the LCR meter are 265mm (width) x 305mm (depth) x 105mm (height).
5. Setup
5.1. Adjusting the Handle
To adjust the handle, hold the handles on both sides of the unit and pull them outward. Then, rotate the handle to the desired position for optimal viewing or portability.
Figure 6: Handle Adjustment.
5.2. Power Connection
Connect the provided three-core power cord to the voltage jack on the rear panel. Ensure the voltage selection switch is set to the correct voltage (110V or 220V) for your region before powering on the device.
5.3. Connecting Test Leads
Plug the Kelvin test cables into the corresponding color-coded ports on the front panel. Ensure a secure connection for accurate measurements.
5.4. Calibration
Before taking measurements, it is crucial to perform open circuit and short circuit calibrations for accuracy.
5.4.1. Open Circuit Calibration
- Ensure no test clips are connected to each other or to any component.
- Press the AUTO/R/C/L/Z button to select the desired measurement mode.
- Press and hold the CAL button for 3 seconds to initiate open circuit calibration. The display will show "OPEN" during this process.
5.4.2. Short Circuit Calibration
- Clip the test clips together as shown in the diagram, ensuring the two test clips are placed on the same side of the wired connection.
- Press and hold the CAL button for 3 seconds to initiate short circuit calibration. The display will show "SHORT" during this process.
Video 1: How to Use RuoShui 4090 LCR Meter (Demonstrates test wire connection, open/short circuit calibration, and measurements).
5.5. Backlight Brightness Setting
To adjust the display backlight brightness:
- Turn on the device and enter the measurement display interface.
- Press the SET key to enter the system setting interface.
- Use the Up and Down arrow keys to navigate the cursor to "Brightness Adjustment".
- Use the Left and Right arrow keys to switch the backlight brightness (options: 30%, 50%, 70%, 100%).
Figure 7: Backlight Brightness Setting.
6. Operation
6.1. Basic Measurement
After proper setup and calibration, connect the component to be measured using the Kelvin test clips. The device will automatically identify the component type and display the primary and secondary parameters on the 3.5-inch TFT screen.
6.2. Measurement Speeds
The LCR meter offers three measurement speeds to suit different needs:
- FAST: 10 times/second
- MID: 5 times/second
- SLOW: 2 times/second
Figure 8: Measurement Speed Options.
6.3. Data Logging Function
The instrument includes a data recording function that allows you to capture maximum, minimum, and average measurement values. This feature can operate with automatic or locked ranges.
Figure 9: Data Logging Function.
6.4. Automatic Component Recognition
The LCR meter automatically identifies the type of component being measured, simplifying the measurement process. It also supports comparator sorting and list scanning for efficient component management.
Figure 10: Automatic Component Recognition.
7. Communication Interfaces
The RuoShui 4090 LCR Meter offers versatile communication options for integration with computers and other systems.
- RS232 Interface: Supports SCPI communication protocol for remote control and data transfer.
- USB Interface: Allows for plug-and-play USB storage device connectivity, software upgrades, and communication with a computer for remote control.
- Handler Interface: Facilitates connection to external sorting devices for automated component testing and classification.
Figure 11: Bridge and Computer Connection.
Figure 12: USB Software Upgrade and Remote Control.
8. Specifications
| Feature | VC4090A | VC4090B | VC4090C | VC4091A | VC4091C |
|---|---|---|---|---|---|
| Digits | Main parameter: 5 digits; secondary parameter: 5 digits | ||||
| Measurement Parameter | Main parameter: L/C/R/Z; secondary parameter: X/D/Q/θ/ESR | ||||
| Measurement Range (L) | 0.001μH - 9999H | ||||
| Measurement Range (C) | 0.001pF - 9999μF | ||||
| Measurement Range (R) | 0.0001Ω - 99.99MΩ | ||||
| Basic Accuracy | 0.10% | ||||
| Test Frequency (Hz) | 100~10kHz | 100~20kHz | 100~100kHz | 10~10kHz | 10~100kHz |
| 10 points | 12 points | 16 points | Continuously adjustable (1Hz) | ||
| Measurement Speed | 2 times/second (slow), 5 times/second (medium), 10 times/second (fast) | ||||
| Internal Bias | 0-1500mV adjustable, 1mV stepping | ||||
| Test Level | 100mV, 300mV, 600mV, 1000mV, 1500mV, 2000mV | 0.1V~2V Continuously adjustable (1mV) | |||
| Correction Function | Open circuit correction, short circuit correction | ||||
| Screening Function | The screening limit can be set from -100% to +100% | ||||
| with fixed points of 10%, 25%, 50% | |||||
| Selection of Comparator | Five gear sorting, third gear qualified, one gear failed, one ancillary gear | ||||
| Communication Interface | Standard configuration: USB, RS232 (or 485), Handle interface; | ||||
| Optional: GPIB, USB Host | |||||
| Other | Support DCR, electrolytic capacitor measurement mode, adjustable backlight brightness, optional in English and Chinese | ||||
| Power | AC 200-240V 50-60Hz | ||||
| Fuse | AC 250V 500mA | ||||
| Working Environment | (0-40)℃, relative humidity <80% | ||||
| Storage Environment | -10-50℃, relative humidity <80% | ||||
| Size (W x D x H) | 265mm x 305mm x 105mm | ||||
| Weight | <2kg | ||||
| Power Consumption | <10W | ||||
9. Maintenance
To ensure the longevity and optimal performance of your RuoShui 4090 Digital LCR Meter, please follow these maintenance guidelines:
- Cleaning: Regularly clean the exterior of the instrument with a soft, dry cloth. Avoid using abrasive cleaners or solvents that could damage the casing or display.
- Storage: Store the device in a clean, dry environment within the specified storage temperature and humidity ranges (-10-50℃, relative humidity <80%).
- Power: Always ensure the correct voltage is selected (110V/220V) before connecting to power.
- Fuses: The device uses an AC 250V 500mA fuse. If the fuse needs replacement, ensure you use a fuse with the identical specifications.
- Batteries: This device is mains-powered and does not use internal batteries for operation, thus no battery maintenance is required.
- Handling: Handle the instrument with care to prevent physical damage.
10. Troubleshooting
This section provides solutions to common issues you might encounter with your LCR meter.
- No Power:
- Check if the power cord is securely connected to both the instrument and the power outlet.
- Verify that the voltage selection switch on the rear panel matches your local power supply (110V/220V).
- Check the fuse. If blown, replace it with a fuse of the same rating (AC 250V 500mA). - Inaccurate Measurements:
- Ensure that open circuit and short circuit calibrations have been performed correctly before measurement.
- Check that the Kelvin test cables are properly connected and not damaged.
- Make sure the component is securely connected to the test clips.
- Verify that the measurement frequency and test level settings are appropriate for the component being tested. - Display Issues:
- If the display is too dim or bright, adjust the backlight brightness through the system settings (refer to Section 5.5).
- If the display is blank or frozen, try restarting the instrument. - Communication Problems (USB/RS232):
- Ensure the correct drivers are installed on your computer.
- Check the physical cable connections.
- Verify that the communication settings (e.g., baud rate) on both the instrument and the computer are correctly configured.
If you encounter an issue not listed here or if the problem persists after attempting these solutions, please contact customer support.
11. Warranty and Support
11.1. Warranty Information
RuoShui (Victor) instruments are guaranteed to be 100% genuine and original. All products come with a 1-year warranty from the date of receipt. Accessories are covered by a 3-month warranty. This warranty does not cover items damaged due to misuse or improper handling.
Defective items must be reported and returned within the warranty period, preferably in their original packaging.
11.2. Customer Support
Should you encounter any problems with your RuoShui 4090 Digital LCR Meter, please contact our customer support team. We are committed to providing the best possible solution to ensure your satisfaction.
12. User Tips
- For highly accurate measurements, always perform both open circuit and short circuit calibrations before testing components, especially when changing test leads or measurement frequencies.
- Utilize the data logging function (MAX, MIN, AVG) for analyzing component stability or variations over time.
- When measuring very small or very large values, consider using the appropriate measurement speed (FAST for quick checks, SLOW for higher precision).
- Keep the instrument's communication interfaces (USB, RS232) clean and protected when not in use to ensure reliable connectivity.
