Instruction Manual: Display Replacement for FLUKE 87 / 87-III / Kent-Moore J-39200 Digital Multimeter

1. Introduction

This manual provides detailed instructions for replacing the display unit of compatible FLUKE 87, FLUKE 87-III, and Kent-Moore J-39200 Digital Multimeters. This replacement display is designed to resolve common issues such as segment fading, missing characters (often referred to as "ghosting"), cracked screens, or black blotches, restoring your multimeter's functionality and readability.

This product is intended for DIY repair and does not require soldering, making the installation process straightforward and quick, typically completable within 10 minutes.

2. Compatibility

• Compatible Models: FLUKE 87, FLUKE 87-III, Kent-Moore J-39200 Digital Multimeter.
• NOT Compatible With: Fluke 87V, 86, 88, 83, 85, or any other versions not explicitly listed as compatible.
• Before purchasing and installation, it is crucial to compare the full display pattern of your existing multimeter with the provided images of this replacement display to ensure compatibility.

Image: Display replacement for FLUKE 87 87-III Digital Multimeter.

Image: Display replacement for FLUKE Kent-Moore J-39200 Digital Multimeter.

3. Product Features

• Direct replacement for original display units.
• Resolves common display issues: fading, missing segments, ghosting, cracks, and black blotches.
• No soldering required for installation.
• Quick installation process (approximately 10 minutes).
• Screen Size: 70mm x 42mm.

Image: The replacement LCD display with its dimensions indicated (70mm x 42mm).

4. Package Contents

The package includes the following items:

• 1 x LCD Display Unit
• 2 x Elastomeric Zebra Connector Rubber Strips

Note: The digital multimeter shown in application scenario images is for instructional purposes only and is not included in the sale.

Image: Front view of the LCD Display Unit.

Image: LCD Display with Elastomeric Zebra Connector Rubber Strips (angled view).

Image: LCD Display with Elastomeric Zebra Connector Rubber Strips (back view).

5. Installation Instructions (Setup)

This display replacement is designed for easy DIY installation without the need for soldering. Please follow these steps carefully:

1. Power Off and Disassemble: Ensure your multimeter is completely powered off and disconnect any probes or cables. Carefully open the multimeter casing according to its specific model's service manual or common disassembly procedures.
2. Locate and Remove Old Display: Identify the existing LCD display unit. Gently disconnect it from the circuit board. Note the orientation of the old display and its associated elastomeric connectors (zebra strips).
3. Clean Contact Areas: Lightly clean the contact areas on the multimeter's circuit board where the elastomeric strips make contact. Use a lint-free cloth and isopropyl alcohol if necessary, ensuring no residue remains.
4. Position New Elastomeric Strips: Place the two new elastomeric zebra connector rubber strips into their designated slots on the circuit board. Ensure they are correctly aligned.
5. Install New LCD Display: Carefully place the new LCD display unit onto the elastomeric strips, ensuring proper alignment with the circuit board contacts. One edge of the LCD may have a small bump in the glass; this bump should typically be oriented to the right when facing the meter.
6. Secure and Reassemble: Gently press down on the display to ensure good contact with the zebra strips. Reassemble the multimeter casing, ensuring all screws are tightened appropriately. Do not overtighten.
7. Test Functionality: Power on your multimeter and verify that the new display functions correctly, showing clear, complete digits without fading or ghosting.

The entire process typically takes around 10 minutes.

6. Operating Considerations

Once installed, the new display operates identically to the original. No special operating procedures are required for the display itself.

Important Note on Backlighting: The backlighting feature on 87 series Multimeters is a separate plug-in incandescent green lamp module and a discrete circuit. This replacement display unit has no connection to the backlighting's color or operation. If your multimeter's backlight is not functioning, this display replacement will not resolve that issue.

7. Maintenance

The LCD display unit requires minimal maintenance. To ensure longevity and clear visibility:

• Clean the display surface with a soft, lint-free cloth.
• Avoid using abrasive cleaners or solvents, which can damage the display surface.
• Protect the multimeter from excessive impact or pressure on the display area.

8. Troubleshooting

This section addresses common issues that the display replacement is designed to fix, as well as potential post-installation concerns.

Image: Before and After comparison for Fluke 87 display issues.

Image: Before and After comparison for Fluke Kent-Moore J-39200 display issues.

9. Specifications

10. Warranty and Support

Information regarding product warranty and customer support is not provided in this manual. For any inquiries regarding warranty or technical assistance, please refer to the product listing on the retailer's website or contact the seller directly.