ASA HW-210K Dual Channel VI Curve Tester User Manual

1. Introduction

The ASA HW-210K is a versatile, handheld VI curve tester designed for the online detection and analysis of circuit boards. This device allows for non-powered circuit board testing by generating characteristic voltage-current (VI) curves, which can be displayed on an oscilloscope. It features dual-channel input, four adjustable test frequencies, and is compatible with both analog and digital oscilloscopes, making it an essential tool for electronics repair and diagnostics.

2. Safety Information

Please read and understand the following safety precautions before operating the HW-210K tester to prevent damage to the device, the circuit board under test, or personal injury.

• Do not test powered circuit boards: The HW-210K is designed for online detection of non-powered circuit boards. Applying the tester to a live circuit board can cause severe damage to both the tester and the circuit board, and poses an electrical shock hazard.
• Discharge capacitors: Before testing any circuit board, ensure that all large capacitors are fully discharged. Residual charge in capacitors can damage the VI tester.
• Use appropriate power supply: The device requires a 24V DC power supply. Ensure the power adapter (not included) meets this specification and has the correct polarity.
• Handle probes carefully: Always hold the probes by their insulated bodies. Avoid touching the metal tips during operation.
• Environmental conditions: Operate the device in a dry environment, away from liquids and excessive dust.

3. Product Overview

3.1 Package Contents

The HW-210K package typically includes:

• 1 x ASA HW-210K VI Curve Tester Unit
• 2 x Test Probes (red and black)
• 2 x BNC to BNC Cables

Note: A 24V DC power adapter is required but not included in the package.

3.2 Device Layout and Controls

Figure 1: Front Panel of the HW-210K Tester

Figure 2: Top Panel of the HW-210K Tester

4. Setup

Follow these steps to set up your ASA HW-210K VI Curve Tester:

1. Power Connection: Connect a 24V DC power adapter (not included) to the power input jack on the top of the HW-210K unit.
2. Oscilloscope Connection:
   • Connect one end of a BNC cable to one of the BNC output connectors on the top of the HW-210K. Connect the other end to the X-input (horizontal) of your oscilloscope.
   • Connect the second BNC cable to the other BNC output connector on the HW-210K and to the Y-input (vertical) of your oscilloscope.
   

   Figure 3: HW-210K connected to an oscilloscope for testing.

3. Probe Connection:
   • Connect the red test probe to the 'A' (red) terminal.
   • Connect the black test probe to the 'COM' (black) terminal.
   • If using dual-channel testing, connect an additional probe (or the blue probe if provided) to the 'B' (blue) terminal.
   

   Figure 4: HW-210K with probes and BNC cables connected.

4. Oscilloscope Settings:
   • Set your oscilloscope to X-Y mode.
   • Adjust the vertical (Y) and horizontal (X) sensitivity (Volts/Div) to an appropriate range, typically starting with 1V/Div or 2V/Div.
   • Ensure the oscilloscope inputs are set to DC coupling.

5. Operating Instructions

Once the setup is complete, you can begin testing circuit boards.

1. Prepare the Circuit Board: Ensure the circuit board to be tested is completely unpowered and any large capacitors are discharged.
2. Select Test Frequency: Press one of the frequency buttons (LOW, MED1, MED2, HIGH) to select the desired test frequency. Different frequencies can reveal different characteristics of components.
3. Adjust AC Speed: Use the rotary knob to adjust the amplitude (AC speed) of the test signal. This can help in obtaining a clearer VI curve on the oscilloscope.
4. Single Channel Testing:
   • Press the 'A' button to select Channel A.
   • Place the black (COM) probe on a known ground point or common reference point of the circuit board.
   • Use the red (A) probe to touch various test points or component pins on the circuit board. Observe the VI curve displayed on the oscilloscope.
   • Compare the observed curve with known good curves or expected component characteristics to identify faults.
5. Dual Channel / Alternate Display Testing:
   • Connect the blue (B) probe to the 'B' terminal.
   • Press the 'A' button for Channel A, 'B' button for Channel B, or press both 'A' and 'B' simultaneously (if supported by the device's logic) for alternate display.
   • This mode is useful for comparing the VI curves of two identical components (one known good, one suspected faulty) or two different points on the same circuit simultaneously.
   • Place the black (COM) probe on a common ground. Use the red (A) probe on one test point and the blue (B) probe on another.
6. Interpreting VI Curves:
   • A straight line indicates a resistive component.
   • An ellipse indicates a capacitive or inductive component.
   • A vertical line indicates a short circuit.
   • A horizontal line indicates an open circuit.
   • Diodes and transistors will show characteristic non-linear curves.
   • Deviations from expected curves indicate a fault.

6. Maintenance

• Cleaning: Use a soft, dry cloth to clean the exterior of the tester. Do not use abrasive cleaners or solvents.
• Storage: Store the device in a cool, dry place away from direct sunlight and extreme temperatures.
• Probe Care: Inspect test probes and cables regularly for any signs of damage (frayed wires, cracked insulation). Replace damaged accessories immediately to ensure safe and accurate operation.
• Power Adapter: Always disconnect the power adapter when the device is not in use for extended periods.

7. Troubleshooting

• No VI Curve on Oscilloscope:
  • Check if the HW-210K is powered on and receiving 24V DC.
  • Verify BNC cable connections between the tester and the oscilloscope's X and Y inputs.
  • Ensure the oscilloscope is set to X-Y mode.
  • Adjust the oscilloscope's Volts/Div settings for both X and Y channels.
  • Confirm probes are securely connected to the tester and making good contact with the circuit board.
• Distorted or Unstable VI Curve:
  • Ensure the circuit board under test is completely unpowered and all large capacitors are discharged.
  • Try adjusting the AC speed rotary knob on the HW-210K.
  • Experiment with different test frequencies (LOW, MED1, MED2, HIGH).
  • Check for loose connections in probes or BNC cables.
• Tester Not Responding:
  • Verify the 24V DC power supply is correctly connected and functioning.
  • Ensure the power adapter meets the 24V DC specification.

8. Specifications

9. User Tips

• Reference Known Good Boards: For effective troubleshooting, always try to have a known good circuit board of the same type available. Comparing the VI curves between a good board and a faulty one is the most reliable method for fault identification.
• Vary Test Frequencies: If a fault isn't immediately apparent, try cycling through the different test frequencies (LOW, MED1, MED2, HIGH). Some component issues might be more visible at specific frequencies.
• Adjust AC Speed: The AC speed knob controls the amplitude of the test signal. Adjusting this can help in scaling the VI curve appropriately on your oscilloscope screen, making details clearer.
• Systematic Testing: When testing a complex circuit board, work systematically. Start from the power input and move towards functional blocks, comparing curves at each stage.

10. Warranty and Support

For any technical assistance, troubleshooting beyond this manual, or warranty inquiries, please contact the seller or manufacturer directly. Keep your purchase records for reference.