1. Producte acabatview
The Extech PH90 Waterproof pH Meter is a precision instrument designed for accurate pH measurement across various applications, including water quality testing, hydroponics, aquaculture, swimming pools, beverage production, and laboratory use. This device features a robust waterproof housing, a replaceable electrode, 3-point automatic calibration, and auto buffer recognition for ease of use and reliable results. Its compact design makes it suitable for both field and professional environments.

Figure 1: Extech PH90 Waterproof pH Meter. This image shows the compact, handheld pH meter with its digital display and control buttons, ready for use.
2. Característiques clau
- Reliable pH Testing: Provides quick and accurate pH measurements for various liquids and semi-solids.
- Ampli rang de mesura: Covers a full 0-14 pH range, suitable for diverse applications.
- Calibració automàtica: Features 3-point automatic calibration with auto buffer recognition for consistent accuracy.
- Disseny durador i impermeable: Built to withstand wet conditions, ideal for fieldwork and outdoor use.
- Replaceable Electrode: Extends the device's lifespan and ensures long-term reliability.
- Pantalla LCD clara: Easy-to-read digital results, including pH and temperature, even in varying light conditions.
- Integrated Temperature Measurement: Built-in temperature sensor for accurate readings.
3. Configuració i preparació
3.1. Instal·lació de la bateria
The PH90 meter requires two CR2032 Lithium Metal batteries (included). To install or replace batteries:
- Desenrosqueu la tapa del compartiment de la bateria que es troba a la part superior del mesurador.
- Insert the two CR2032 batteries, ensuring correct polarity (+/-).
- Securely screw the battery compartment cap back into place.
3.2. Electrode Preparation
Before first use, and after storage, prepare the electrode:
- Remove the protective cap from the electrode tip. The cap contains a moist sponge to keep the electrode hydrated.
- Rinse the electrode tip thoroughly with distilled or deionized water. Do not wipe the electrode, as this can create static charges.
- Allow any excess water to drip off.
3.3. Calibració inicial
For optimal accuracy, perform a 3-point calibration before initial use and periodically thereafter. Calibration buffers (pH 4, 7, and 10) are sold separately.
- Engegueu el mesurador prement el botó ON/OFF botó.
- Immerse the electrode into a pH 7.00 buffer solution.
- Manteniu premut el botó CAL button until "CAL" appears on the display. The meter will automatically recognize the buffer and calibrate.
- Esbandiu l'elèctrode amb aigua destil·lada.
- Repeat the process with pH 4.00 and pH 10.00 buffer solutions. The meter will automatically detect and calibrate to these points.
- Un cop finalitzada la calibració, el mesurador tornarà al mode de mesura.

Figure 2: Close-up of the Extech PH90 display and control buttons, including ON/OFF, MODE, and CAL buttons.
4. Instruccions de funcionament
4.1. Prendre una mesura
- Assegureu-vos que el mesurador estigui calibrat.
- Rinse the electrode with distilled water and gently shake off excess.
- Submergiu la punta de l'elèctrode a la sampla solució, assegurant-vos que el sensor estigui completament submergit.
- Gently stir the solution to ensure homogeneity and allow the reading to stabilize. This may take up to a minute, especially if the sample temperature differs significantly from the meter's previous environment.
- Read the pH value displayed on the LCD screen. The temperature will also be displayed.
- Després de la mesura, esbandiu bé l'elèctrode amb aigua destil·lada.
4.2. Funció Hold
Per congelar la lectura actual a la pantalla, premeu la tecla MANTENIM button (if available, typically integrated with MODE or a separate button). Press it again to release the hold and return to live measurement.
4.3. Compensació automàtica de temperatura (ATC)
The Extech PH90 features Automatic Temperature Compensation, which adjusts pH readings based on the sample's temperature, ensuring accuracy across varying temperatures. The temperature is displayed alongside the pH value.
5. Manteniment
5.1. Cura i emmagatzematge d'elèctrodes
Proper electrode care is crucial for maintaining accuracy and extending the life of your meter:
- Always keep the electrode tip moist. Store the meter with the protective cap filled with electrode storage solution or pH 7 buffer solution. Never store in distilled or deionized water, as this can deplete the electrode's electrolyte.
- Rinse the electrode thoroughly with distilled water after each use.
- If the electrode becomes dirty or readings are sluggish, clean it using a mild electrode cleaning solution. Follow the cleaning solution manufacturer's instructions.

Figure 3: Close-up of the Extech PH90's replaceable electrode tip, which requires proper care and storage.
5.2. Substitució d'elèctrodes
The PH90 features a replaceable electrode. If the electrode performance degrades significantly despite proper cleaning and calibration, it may need replacement. Refer to the Extech weblloc web o poseu-vos en contacte amb l'atenció al client per obtenir informació sobre la compraasing replacement electrodes (Part PH95).
5.3. Substitució de la bateria
When the battery indicator appears on the display or the meter fails to power on, replace the two CR2032 Lithium Metal batteries as described in Section 3.1.
6. Solució De Problemes
| Problema | Causa possible | Solució |
|---|---|---|
| Lectures inexactes o inestables |
|
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| El comptador no s'encén |
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| "CAL" error during calibration |
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7. Especificacions
| Paràmetre | Valor |
|---|---|
| Número de model | PH90 |
| Rang de pH | 0 a 14 pH |
| Precisió del pH | ±0.01 pH |
| Interval de temperatura | (Not explicitly stated, but integrated for ATC) |
| Font d'alimentació | 2 x CR2032 Lithium Metal batteries |
| Pes de l'article | 2.88 unces (aproximadament 81.6 grams) |
| Dimensions del producte | 6.7 x 1.4 x 1.4 polzades (aprox. 17 x 3.6 x 3.6 cm) |
| Components inclosos | Flat surface pH electrode, cap, batteries (pH buffers sold separately) |
| Fabricant | Extech |
8. Garantia i Suport
For warranty information, technical support, or to purchase replacement parts and accessories, please visit the official Extech website or contact Extech customer service. You can also find more information and products at the Botiga Extech a Amazon.





