Horiba Scientific LAQUAact D-71G User Manual (English)

Questions and Answers:

C
Christopher BrandtAug 17, 2025
Why is the response slow on my Horiba Scientific Measuring Instruments?
- N
  Nicole HancockAug 17, 2025
  A slow response on your Horiba Scientific Measuring Instruments could be due to a few reasons. The electrode might be dirty or cracked, so try cleaning or replacing it. Also, ensure you are using the correct internal solution. Additionally, the sample solution may be affecting the electrode's response. In that case, it is important to select an electrode that is appropriate for the sample. Consult your dealer.
R
Russell JamesAug 21, 2025
What to do if nothing appears when I turn on my Horiba Scientific LAQUAact D-71G Measuring Instruments?
- W
  williamsjessicaAug 21, 2025
  If nothing appears when you turn on your Horiba Scientific Measuring Instruments, check the following: * Ensure that the power is supplied by inserting batteries or connecting the AC adapter (if available). * Verify that the battery polarity (+, -) is correct. * If using batteries, try replacing them or use the AC adapter, as the battery life may be low.
T
Tommy JohnsonAug 26, 2025
Why is the measured value blinking on my Horiba Scientific Measuring Instruments?
- Q
  qhartmanAug 26, 2025
  If the measured value is blinking on your Horiba Scientific Measuring Instruments, consider these potential causes. The sample might be outside the measurement range, so use a sample within the appropriate range. Ensure the electrode is immersed enough to cover the liquid junction, ideally to at least 3 cm from the tip. A broken electrode cable could also be the issue, so replace the electrode if necessary. Also, make sure that the calibration is performed correctly. If not, repeat the calibration procedure.
T
turnerianAug 29, 2025
How to improve the repeatability of measured values on Horiba Scientific Measuring Instruments?
- K
  Kenneth Gordon DDSAug 29, 2025
  Poor repeatability of the measured value on your Horiba Scientific Measuring Instruments can stem from several causes. The pH of the sample may be changing over time. Clean the electrode (Electrode cleaning solution 220 or 250 is recommended), as it may be dirty. Also, the electrode may be cracked and needs replacement. Ensure the internal solution of the electrode is not running out or contaminated; replace it if needed. Finally, check that the level of internal solution in the reference electrode is higher than the level of the sample; replenish if low.
M
michelle90Sep 1, 2025
Why is the temperature display blinking or fixed at 25°C on my Horiba Scientific LAQUAact D-71G?
- N
  Nicholas HoldenSep 1, 2025
  If the temperature display on your Horiba Scientific Measuring Instruments blinks or is fixed at 25°C, it could be due to several reasons. First, ensure the sample temperature is within the measurement range. Next, check that the temperature connector is correctly connected. If the temperature setting is set to MTC, change it to ATC. Incorrect operation during temperature calibration can also cause this issue; recalibrate using a solution of known temperature, or return to the factory setting.
D
Danny SharpSep 5, 2025
What to do if the indicated value does not change on Horiba Scientific LAQUAact D-71G?
- J
  Julie PowersSep 5, 2025
  If the indicated value on your Horiba Scientific Measuring Instruments does not change or there is no response, check the following: The electrode may be cracked, so replace it. Ensure the electrode is correctly connected. If the keys are locked, turn off the power, remove the batteries, and then turn on the power again. Also, verify that the instrument is not in HOLD state and cancel it if it is.
C
Christina BryantSep 9, 2025
Why is there swelling of the operation key sheet on my Horiba Scientific LAQUAact D-71G Measuring Instruments?
- M
  Michael SolisSep 9, 2025
  If you notice swelling of the operation key sheet on your Horiba Scientific Measuring Instruments, it might be due to using the instrument at a high elevation or another location where the air pressure differs from sea level. To address this, briefly open and then close the AC adapter cover to equalize the pressure. Ensure the cover is correctly closed afterward to maintain dust and water proofing.

Horiba Scientific LAQUAact D-71G Specifications

General

pH Range	0.00 to 14.00 pH
pH Resolution	0.01 pH
pH Accuracy	±0.01 pH
mV Resolution	1 mV
mV Accuracy	±1 mV
Temperature Resolution	0.1 °C
Temperature Accuracy	±0.5 °C
Calibration Points	Up to 5 points
Data Memory	500 data sets
Display	LCD with backlight
Power	2 x AA batteries
Waterproof	IP67
Communication Interface	USB
ORP Resolution	1 mV
ORP Accuracy	±1 mV
Salinity Resolution	0.01 ppt
Type	Water Quality Meter
Temperature Range	0 to 100 °C
Operating Conditions	0 to 50 °C, 85% RH or less
Storage Conditions	–20 to 60 °C, 85% RH max
ORP Range	±1999 mV
Conductivity Range	0.00 to 199.9 mS/cm
Conductivity Accuracy	±1% of reading
Resistivity Accuracy	±1% of reading
TDS Accuracy	±1% of reading

Summary

Preface

Warranty and Responsibility

Details HORIBA's warranty terms and limitations for the product.

Trademarks

Lists company names and brand names as registered or trademarked.

Check Items

Items in Package

Ensures all standard accessories are present after opening the package.

Regulations

EU Regulations and Conformable Standards

Lists EU standards (EMC, Safety, RoHS) the equipment conforms to.

Installation Environment Requirements

Specifies the voltage category and pollution degree the product is designed for.

Disposal Information

Provides guidance on proper disposal of electrical equipment and batteries.

FCC and Korea Certification

Details FCC rules and Korea certification compliance for the device.

China Regulation and Marking Meaning

Explains Chinese regulations and the meaning of environmental protection marking.

Hazardous Substance Information

Lists the amount of hazardous substances used in the product components.

For Your Safety

Hazard Classification and Warning Symbols

Explains the meaning of DANGER, WARNING, CAUTION and symbol types.

Multilingual Safety Information

Provides safety information in French, Italian, and Swedish.

Safety Precautions and Warnings

Outlines essential safety measures for instrument, electrode, chemicals, and battery.

Product Handling Information

Operational Precautions

Covers safe operation, handling, and precautions for instrument and battery.

Environmental Conditions for Use and Storage

Specifies temperature, humidity, and environmental factors to avoid.

Transportation and Disposal

Details safe transportation and proper disposal procedures for the instrument.

Manual Information

Description of Manual Elements

Explains the meaning of Note, Reference, Tip, and Original Language indicators.

Part Names and Basic Operation

Names of Each Part

Details the instrument's components and their functions.

Basic Operation Guide

Explains how to change modes and enter numeric values on the instrument.

Measurement

Preparation for Measurement

Covers electrode and standard solution preparation, and setup checks.

pH Measurement Procedure

Guides on setting the instrument, calibration, and performing pH measurements.

Performing Calibration

Details the steps for accurate pH calibration using standard solutions.

How to Resolve Errors or Troubles

Error Message Identification

Lists error codes and their definitions for instrument faults.

Troubleshooting Common Issues

Provides causes and solutions for fluctuating values, slow response, and no response.

Using Various Functions

Data Management Functions

Covers saving, displaying, and deleting measurement and calibration data.

Instrument Setting and Configuration

Explains ID setting, calibration interval alarm, and auto power off configuration.

Sensor Calibration and System Reset

Details calibrating the temperature sensor and resetting to factory defaults.

Appendix

Main Specifications

Lists key technical specifications like model, power, dimensions, and mass.

Instrument Default Settings

Details the factory default values for various instrument settings.

Technical Note

pH Measurement Principle (Glass Electrode)

Explains the electromotive force principle behind pH measurement with glass electrodes.

pH Standard Solution Values

Provides pH values for standard solutions at various temperatures for calibration.

For More Information

Website Resources and User Registration

Directs users to the website for detailed information and user registration benefits.

Options

Available Electrodes and Accessories

Lists various electrodes and options with part numbers and remarks for purchase.

Related product manuals

Horiba Scientific LAQUA F-72

Horiba Scientific LAQUAact D-71G User Manual

Table of Contents