1、 Preparation work

1. Tool Preparation

• Special screwdriver (flat/cross)

• alcoholOr precision instrument cleaner

• Dust free cloth/cotton swab

• Anti-static gloves

• Electronic maintenance platform (anti-static)

2. Safety Precautions

• Keep the workbench clean and dry

• Avoid environments with strong static electricity

• Handle precision components with care

2、 Common fault diagnosis

Fault 1: Display abnormality/not displaying

Possible reasons：

• Low battery level

• Poor battery contact

• The motherboard is damp

Repair steps：

1. Replace with a new battery (SR44 type)

2. Clean the battery compartment contacts with a cotton swab dipped in alcohol

3. Check the motherboard for corrosion, mild corrosion can be cleaned with alcohol

Fault 2: Unstable measurement value/hop count

Possible reasons：

• The ruler has stains

• Sensor is dirty

• Wear of conductive strip

Repair steps：

1. Take out the ruler and wipe it unidirectionally with a dust-free cloth dipped in alcohol

2. Clean the sensor contact area (to avoid scratches)

3. Check the conductive strip, and gently wipe it with an eraser if there is slight wear

Fault 3: Button malfunction

Possible reasons：

• Oxidation of key contact points

• Button film damaged

Repair steps：

1. Clean the button contacts with a cotton swab dipped in alcohol

2. If the button film is damaged, it needs to be replaced (professional accessories are required)

Fault 4: Smooth sliding

Possible reasons：

• There are impurities in the orbit

• Insufficient lubrication

Repair steps：

1. Clean the track with air blowing

2. Drip a small amount of precision instrument lubricating oil (avoid excessive)

3、 Precautions for disassembly and assembly

Disassembly steps:

1. Remove the battery

2. Remove the screws on the back (pay attention to the screw specifications and order)

3. Gently separate the shell

4. Record the position of each component (can be photographed)

Assembly points:

1. Confirm that all components are clean

2. Install in sequence

3. Tighten the screws evenly (avoid over tightening)

4、 Calibration method

1. Zero calibration：

• Clean the measuring surface and close the caliper

• Press and hold the "ZERO" button until it displays "zero"

2. accuracy verification：

• Use standard measuring blocks

• Multi point measurement verification of linearity

5、 Daily maintenance suggestions

1. after useClean the measuring surface and loosen the locking screw

2. storePut it in a dedicated box to avoid squeezing

3. regularlyCheck the battery and clean the track every quarter

6、 Maintenance restriction prompt

⚠️It is recommended to return to the factory for repair in the following situations：

• LCD screen rupture

• The main ruler is noticeably bent

• Chip level malfunction

• Depth gauge damaged

7、 Precautions

1. Non professionals are not allowed to disassemble sensors and display screens

2. Avoid using organic solvents (such as gasoline, acetone)

3. Basic accuracy verification is required after maintenance

Simple maintenance can solve 80% of common problems, but precise adjustments still require professional equipment. If unsure, it is recommended to contact a repair center.

If you have technical support (maintenance), please contact: Nal Industrial Equipment (Suzhou) Co., Ltd