1. Introducció
The BENETECH GM8906 Digital Contact Motor Tachometer is a portable, high-precision instrument designed for measuring rotational speed (RPM) and linear velocity. It features a high-definition LCD backlight display, automatic shutdown, and low power indication for user convenience. The device utilizes a high-sensitivity contact probe combined with an upgraded microprocessor and internal components to ensure accurate and reliable measurements across various applications.

2. Informació de seguretat
Please read this manual thoroughly before operating the device to ensure safe and proper use. Keep this manual for future reference.
- No intenteu desmuntar ni modificar el dispositiu. Les modificacions no autoritzades poden provocar un mal funcionament o lesions.
- Ensure the device is used within its specified operating environment (temperature and humidity).
- Eviteu exposar el dispositiu a temperatures extremes, llum solar directa o humitat elevada.
- Mantingueu el dispositiu allunyat de camps electromagnètics forts.
- Handle the contact probe with care to prevent damage.
- This device is not waterproof; avoid contact with liquids.
- When replacing batteries, ensure the device is turned off and use the correct battery type and polarity.
- Desfeu-vos de les piles i del dispositiu d'acord amb la normativa local.

3. Components del producte
The BENETECH GM8906 tachometer typically includes the main unit and several interchangeable contact heads to suit various measurement needs.
- Unitat principal: The handheld device with LCD display and control buttons.
- Contact Heads:
- Small Conical Tachometer Head
- Large Conical Rotating Head
- Cylindrical Tachometer Head
- Linear Speed Head


4. Configuració
4.1 Instal·lació de la bateria
The GM8906 requires 2 AAA 1.5V batteries (not included). To install:
- Localitzeu el compartiment de la bateria a la part posterior del dispositiu.
- Obriu la tapa de la bateria.
- Introduïu 2 piles AAA, assegurant-vos de la polaritat correcta (+/-).
- Tanqueu la tapa de la bateria amb seguretat.
Note: Shipping regulations often prohibit the inclusion of liquids, powders, and dry batteries. Please purchase batteries separately.
4.2 Attaching Contact Head
Select the appropriate contact head for your measurement task. Gently push the desired head onto the metal shaft at the top of the tachometer until it is firmly seated.
5. Instruccions de funcionament
5.1 Dispositiu acabatview

- Menu Key (MEM): Used to access memory functions (MAX/MIN/AVG/LAST values).
- Start/Close Measurement Key (Power/Measure): Press to start or stop measurement.
- Switch On/Off/Backlight Key (Lightbulb/Power): Press to turn on/off the device or toggle the backlight.
5.2 Encès/Apagat
- Premeu el botó Switch On/Off/Backlight Key per encendre el dispositiu.
- The device will automatically shut down after 60 seconds of inactivity to conserve battery life.
- Per apagar manualment, premeu i manteniu premut el botó Switch On/Off/Backlight Key.
5.3 Prendre mesures
The GM8906 is designed for contact measurement of rotational speed (RPM) and linear velocity. It supports measuring objects such as engines, fans, washing machines, and ships.

- Select Appropriate Head: Choose the contact head that best suits the surface or shaft of the object you are measuring.
- Encès: Turn on the tachometer using the Switch On/Off/Backlight Key.
- Iniciar la mesura: Premeu el botó Start/Close Measurement Key.
- Contact Surface: Gently press the selected contact head against the rotating part of the object. Ensure firm and stable contact for accurate readings.
- Visualització de lectura: The RPM or linear velocity will be displayed on the LCD screen.
- Stop Measurement: Allibera el Start/Close Measurement Key to stop the measurement.
5.4 Data Hold and Memory Functions
The device supports holding the maximum, minimum, average, and last measured values.
- While a measurement is active, press the Menu Key (MEM) to cycle through MAX, MIN, AVG, and LAST readings.
- The current reading will be held on the display until the measurement is stopped or a new measurement is initiated.
5.5 Demostració en vídeo
Watch this video for a visual guide on operating the BENETECH GM8906 Digital Contact Motor Tachometer:
6. Manteniment
6.1 Neteja
- Netegeu el dispositiu amb un drap suau i sec. No utilitzeu productes de neteja abrasius ni dissolvents.
- Keep the contact probe clean and free from debris to ensure accurate readings.
6.2 Emmagatzematge
- Quan no les feu servir durant períodes prolongats, traieu les piles per evitar fuites.
- Guardeu el dispositiu en un lloc fresc i sec, allunyat de la llum solar directa i de temperatures extremes.
- Keep the contact heads organized and protected from damage.
6.3 Substitució de la bateria
When the low battery indicator appears on the LCD, replace the batteries promptly to ensure continued accurate operation.
7. Solució De Problemes
| Problema | Causa possible | Solució |
|---|---|---|
| El dispositiu no s'encén | Bateries gastades o mal instal·lades | Canvieu les piles, assegurant-vos de la polaritat correcta. |
| Lectures inexactes | Loose contact with object; dirty probe; damaged probe | Ensure firm contact; clean probe; replace damaged probe. |
| LCD display is dim or flickering | Potència de bateria baixa | Substituïu les piles. |
| El dispositiu s'apaga de manera inesperada | Automatic shutdown activated; low battery | Press any key to reactivate; replace batteries if low. |
8. Especificacions
| Característica | Detall |
|---|---|
| Número de model | GM8906 |
| Tipus | Tachometer (Contact Type) |
| Nom de marca | BENETECH |
| Pantalla LCD | 5-Digits large screen, Backlight |
| Interval | 0.5-19999 RPM |
| Relació de resolució | 0.1 RPM (0.5-999.9 RPM), 1 RPM (above 19999 RPM) |
| Precisió | ±(0.05% + 1 dgt) |
| SampTarifa ling | 1 segon/temps |
| Distància de mesura | 50-500 mm |
| Base de temps | Cristall de quars |
| Apagat automàtic | Després de 60 segons d’inactivitat |
| Indicació de bateria baixa | Sí |
| Funció de memòria | MAX/MIN/AVG/LAST values |
| Entorn de funcionament | 0~50°C (32~122°F); 10%~90% RH |
| Entorn d'emmagatzematge | (-10)~50°C (-14~122°F); 10%~75% RH |
| Bateria inclosa | No (Requires 2x AAA 1.5V) |
| Certificació | CE |
9. Consells d'usuari
- For best accuracy, ensure the contact head is perpendicular to the rotating surface and applied with consistent, gentle pressure.
- When measuring linear speed, ensure the linear speed head is aligned with the direction of movement.
- Always check the battery level before critical measurements to avoid interruptions.
- Utilize the memory function (MAX/MIN/AVG) to capture peak performance or average speeds over time.
10. Garantia i Suport
BENETECH products are manufactured to high-quality standards. For warranty information, technical support, or service inquiries, please refer to the contact information provided with your purchase documentation or visit the official BENETECH weblloc web. Conserveu el rebut de compra com a comprovant de compra per a reclamacions de garantia.





