1. ആമുഖം
This manual provides detailed instructions for the installation, operation, and maintenance of your DIGITEN 4-Digit Green LED Tachometer RPM Speed Meter. This device is designed to measure rotational speed (RPM) using a Hall proximity switch and magnet sensor, suitable for applications such as lathes, CNC machines, and conveyor belts.
2. പാക്കേജ് ഉള്ളടക്കം
- Tachometer x 1
- Hall NPN proximity sensor x 1
- കാന്തം x 1

Image: Contents of the DIGITEN Tachometer package, including the display unit, Hall sensor, and magnet.
3 സ്പെസിഫിക്കേഷനുകൾ
| പവർ ആവശ്യകത | ഡിസി ക്സനുമ്ക്സ-ക്സനുമ്ക്സവ് |
| പരിധി അളക്കുക | 5-9999 ആർപിഎം |
| പൂജ്യം മായ്ക്കുക | Automatic (approx. 10s, longer for higher RPM) |
| ആവൃത്തി പുതുക്കുക | 0.2-0.5S@120-1200RPM; 0.25-0.06S@2400-9999RPM |
| കൃത്യത അളക്കുക | RPM < 5000, ±2; RPM > 5000, ±3 |
| പ്രദർശിപ്പിക്കുക | Green 0.56 inch LED |
| സിഗ്നൽ തരം | Pulse signal, Hall NPN 3 wires normally closed |
| Hall Proximity Model | NJK-5002D |
| സെൻസർ രൂപഭാവം | M12mm cylinder |
| കണ്ടെത്തൽ പരിധി | 2-3 മി.മീ |
| Proximity Output Current | 200mA |
| Detected Objects | കാന്തം |
| പ്രതികരണ ആവൃത്തി | 100HZ |
| Tachometer Dimension | 72x36x20mm |
| പാനൽ കട്ട്ഔട്ട് അളവ് | 68x33 മി.മീ |
| സെൻസർ അളവ് | M12x37mm |
| പ്രവർത്തന താപനില | 0 മുതൽ 50 ഡിഗ്രി സെൽഷ്യസ് വരെ |

Image: Detailed dimensions of the tachometer display unit, showing length (72mm) and height (36mm).
4. സജ്ജീകരണവും ഇൻസ്റ്റാളേഷനും
4.1 Mounting the Tachometer Display
The tachometer display unit requires a panel cutout for flush mounting. Ensure the cutout dimensions match the specified 68x33mm. Secure the display unit into the panel.
4.2 Mounting the Hall Proximity Sensor and Magnet
- Mount the Hall NPN proximity sensor in a fixed position near the rotating part (e.g., shaft, pulley) whose RPM is to be measured.
- Attach the magnet to the rotating part. Ensure the magnet is securely fixed to prevent detachment during operation.
- Position the sensor so that the magnet passes within its detection range of 2-3mm (0.07"-0.12") during rotation.
- Verify the magnet's orientation. The direction of the magnet relative to the sensor is crucial for proper detection. If the tachometer does not register RPM, try flipping the magnet's orientation.

Image: The Hall proximity sensor, showing its M12mm cylindrical form factor and the attached cable.
5. വയറിംഗ് ഡയഗ്രം
Carefully follow the wiring instructions below to connect the tachometer display to the Hall sensor and power supply. Incorrect wiring can damage the device.
5.1 Hall NPN Proximity Sensor Wiring
- തവിട്ട് വയർ: Connect to Power + (DC positive)
- നീല വയർ: Connect to Power - (DC negative / Ground)
- കറുത്ത വയർ: Connect to Signal output
5.2 Tachometer Display Wiring
- ചുവന്ന വയർ: Connect to DC + (Power positive, 8-15V DC)
- കറുത്ത വയർ: Connect to GND (Ground / Power negative)
- മഞ്ഞ വയർ: Connect to IN+ (Signal input from the sensor's black wire)
Ensure all connections are secure and correctly matched before applying power.

Image: Detailed wiring diagram showing connections between the tachometer display, Hall sensor, and DC power source.
6. ഓപ്പറേഷൻ
Once the tachometer is correctly installed and wired, apply DC power (8-15V). The green LED display will illuminate. As the magnet attached to the rotating part passes the Hall sensor, the tachometer will detect the pulses and display the corresponding RPM value.
- The display will automatically clear to zero after approximately 10 seconds if no pulses are detected. For higher RPM values, the clear zero time may be slightly longer.
- The refresh frequency of the display varies with RPM, providing a responsive reading across the measurement range.
7. പ്രശ്നപരിഹാരവും നുറുങ്ങുകളും
- No RPM Reading or Incorrect Reading:
- Confirm all wires are connected correctly according to the wiring diagram.
- Check the direction of the magnet. If the reading is incorrect or absent, try flipping the magnet.
- Ensure the distance between the magnet and the sensor is within the optimal range of 2-3mm (0.07"-0.12").
- വൈദ്യുതി വിതരണം വോളിയം പരിശോധിക്കുകtage is within the specified DC 8-15V range.
- Display Not Illuminating:
- Check power connections to the tachometer display (Red to DC+, Black to GND).
- വൈദ്യുതി വിതരണം ശരിയായി പ്രവർത്തിക്കുന്നുണ്ടെന്ന് ഉറപ്പാക്കുക.
- ഇടയ്ക്കിടെയുള്ള വായനകൾ:
- Re-check the sensor-to-magnet distance. Vibrations or misalignment can cause inconsistent readings.
- Ensure the magnet is securely attached and not moving relative to the rotating part.
8. വാറൻ്റിയും പിന്തുണയും
DIGITEN provides a one-year warranty term for any product issues. If you encounter any problems or have questions regarding your tachometer, please contact DIGITEN customer support. Refer to the product packaging or purchase documentation for contact details.





