GVDA AR8210 Portable Dissolved Oxygen Meter User Manual

1. Introduction

The GVDA AR8210 is an intellectual, precise measurement apparatus designed with imported components and sensors. It offers high sensitivity, accuracy, and stable performance across various temperatures. This device is capable of measuring dissolved oxygen (DO) values and the solvent's temperature. It is widely applicable in industrial, electrical, agricultural, medical, food, and drinking water quality analysis. Please read this manual thoroughly to ensure correct usage and optimal performance.

2. Product Overview

The meter features a pen-type design, making it portable and easy to carry for on-site operations. It includes a large LCD display with backlight for clear reading.

Key Components:

1. USB Port (for charging)
2. LCD Display
3. Power ON/OFF / Data Hold Button
4. Calibrate / Increase Button
5. Backlight / Reduce Button
6. Dissolved Oxygen Electrode Probe

3. Setup

3.1. Package Contents

Before use, please check the package to ensure all components are present:

• 1x Dissolved Oxygen Meter (Main unit)
• 1x USB Cable
• 1x Dissolved Oxygen Electrode Probe
• 10x A Type Reagent
• 10x B Type Reagent
• 3x Protection Cover
• 1x User Manual (this document)
• 1x Certificate of Calibration
• 1x Cloth Bag

3.2. Battery Charging

The device is powered by a 3.7V Li-polymer rechargeable battery. If the battery indication on the LCD display is empty, the device needs charging.

1. Open the battery door.
2. Plug the USB cable into the meter's USB port and connect it to a power source.
3. A full charge takes approximately 4 hours.

3.3. Probe Preparation and Initial Calibration

The probe must be calibrated before its first use and after prolonged periods of inactivity. It is also recommended to calibrate before any precise measurements.

1. Ensure the probe is dry before calibration.
2. Fill the probe with fresh electrolyte:
   • Take out the new probe reservoir.
   • Fill 3/4 of the reservoir with fresh electrolyte. Ensure there are no bubbles. If bubbles are present, gently pat the probe to remove them.
   • Screw the probe reservoir back onto the probe handle until the membrane touches the gold cathode. Keep the reservoir as bubble-free as possible.
   • If electrolyte overflows, clean it with a soft paper.
3. Plug the probe connector into the main unit.
4. Turn on the device and wait for at least 30 minutes before use.
5. If the probe is immersed in hydrogen peroxide water or saturated dissolved oxygen water and the value changes very little, replace a new probe reservoir and add fresh electrolytes.

4. Operating Instructions

4.1. Power ON/OFF and Data Hold

• Power ON: Short press the Power ON/OFF / Data Hold button.
• Data Hold: After the unit turns on, short press the Power ON/OFF / Data Hold button to hold the measured value.
• Power OFF: Long press the Power ON/OFF / Data Hold button for more than 3 seconds.

4.2. Calibration Procedure (Air Calibration)

The instrument uses an air calibration method. Before calibrating, connect the probe to the host and turn it on for 30 minutes.

1. In normal measurement mode, long press the CAL/▲ button for 3 seconds to enter calibration mode.
2. Place the probe in the air and wait for two to three minutes until the reading stabilizes.
3. Press the CAL/▲ button again until the LCD screen displays "PAS". The instrument will store the setting value and return to normal measurement mode.

Note: If the LCD screen displays "Err" during calibration, it means the calibration failed. This could be due to the value not being within the calibration range or probe damage.

4.3. Compensation Settings (Salinity and Altitude)

If the sample liquid is saline or the test location is not at sea level, perform the following compensation:

1. In normal measurement mode, long press the SET/▼ button to enter compensation setup mode. The LCD will show "TDS" and "Salinity value" flashing.
2. Use the CAL/▲ button to increase the salinity value (long press for faster increase) and the SET/▼ button to reduce the value (long press for faster reduction).
3. After setting the salinity value, press the Power ON/OFF / Data Hold button to save the setting and enter Altitude compensation mode (AP). The LCD will show "AP" and "AP value" flashing.
4. Use the CAL/▲ button to increase the altitude value and the SET/▼ button to reduce the value.
5. To switch altitude units (mmHg and KPa), press CAL/▲ and SET/▼ buttons simultaneously.
6. After setting the altitude value, press the Power ON/OFF / Data Hold button to save the setting and return to normal measurement mode.

4.4. Backlight Control

Short press the SET/▼ button to turn the backlight on or off sequentially.

4.5. Temperature Unit Selection (℃/℉)

1. Before powering on the unit, press and hold both the Power ON/OFF / Data Hold button and the SET/▼ button simultaneously to enter temperature selection mode.
2. The LCD screen will display "℃" or "℉".
3. Short press the Power ON/OFF / Data Hold button to select the desired unit.
4. Long press the Power ON/OFF / Data Hold button to save the selection and return to normal measurement mode.

4.6. Auto Power Off (APO) Setup

1. Before powering on the unit, press and hold both the Power ON/OFF / Data Hold button and the CAL/▲ button simultaneously to enter auto power off setup mode.
2. The LCD screen will display "APO ON" or "APO OFF".
3. Short press the Power ON/OFF / Data Hold button to select "APO ON" (auto power off after 5 minutes of inactivity) or "APO OFF" (no auto power off).
4. Long press the Power ON/OFF / Data Hold button to save the selection and return to normal measurement mode.

5. Maintenance

5.1. Probe and Electrode Maintenance

It is highly recommended to maintain the probe and electrode every six months. Keep the probe clean and its head inside the protection cover when not in use. Periodically clean the electrode and refill the electrolyte with fresh solution.

1. Remove the probe from the instrument.
2. Unscrew the old diaphragm set from the probe head. Clean the metal electrode and old diaphragm with distilled water.
3. If the golden cathode electrode becomes dark, use polish paper with a drop of deionized water to polish its surface (5-10 turns). Clean the golden cathode with deionized water, then dry it with clean paper. Ensure the golden cathode surface becomes bright again.
4. Clean the silver anode electrode. If its surface becomes dark grey, use polish paper to polish it until it becomes bright silver-grey.
5. Add fresh electrolyte (3/4 full) to a new diaphragm, ensuring no air bubbles are present.
6. Screw the new diaphragm onto the electrode until tightened.

Remark: If electrolyte overflows, clean it with a soft paper.

5.2. Electrode Storage

• Short-period storage (overnight or between measurements): Keep the electrode in the instrument and place it into clean water.
• Long-period storage: If the electrode will not be used for a long time, clean it with boiled distilled water, let it cool down, and store it in a dry area. Do not turn on the unit during cleaning. The instrument should be stored in an environment with humidity less than 85% RH and temperature not higher than 40 ℃.

6. Troubleshooting

• "Err" displayed during calibration: This indicates a calibration failure. Possible causes include the value being outside the calibration range or damage to the probe. Refer to section 5.1 for probe maintenance.
• Empty battery indication: The battery needs to be recharged. Refer to section 3.2 for charging instructions.

7. Specifications

8. Application Areas

The GVDA AR8210 Dissolved Oxygen Meter is suitable for a wide range of applications, including:

• Freshwater culture
• Mariculture
• Swimming pools
• Domestic water testing
• Industrial water testing
• Beverage factories
• Wastewater treatment plants
• Laboratories
• Agricultural fields
• Aquaculture
• Pharmaceutical fields

9. Warranty and Support

9.1. Warranty Period

• The composite electrode has a warranty period of one year from the date of purchase.
• Accessories come with a 3-month warranty.

During the warranty period, if any malfunction is found, the manufacturer will repair or replace the item. This warranty does not cover items damaged or misused after receipt.

9.2. Additional Resources

For a detailed user manual and further information, you may refer to the official PDF document: GVDA AR8210 User Manual (PDF).