Inst ToolsInst ToolsInst Tools
  • Courses
  • Automation
    • PLC
    • Control System
    • Safety System
    • Communication
    • Fire & Gas System
  • Instrumentation
    • Design
    • Pressure
    • Temperature
    • Flow
    • Level
    • Vibration
    • Analyzer
    • Control Valve
    • Switch
    • Calibration
    • Erection & Commissioning
  • Interview
    • Instrumentation
    • Electrical
    • Electronics
    • Practical
  • Q&A
    • Instrumentation
    • Control System
    • Electrical
    • Electronics
    • Analog Electronics
    • Digital Electronics
    • Power Electronics
    • Microprocessor
  • Request
Search
  • Books
  • Software
  • Projects
  • Process
  • Tools
  • Basics
  • Formula
  • Power Plant
  • Root Cause Analysis
  • Electrical Basics
  • Animation
  • Standards
  • 4-20 mA Course
  • Siemens PLC Course
Reading: pH sensor calibration procedure
Share
Notification Show More
Font ResizerAa
Inst ToolsInst Tools
Font ResizerAa
  • Courses
  • Design
  • PLC
  • Interview
  • Control System
Search
  • Courses
  • Automation
    • PLC
    • Control System
    • Safety System
    • Communication
    • Fire & Gas System
  • Instrumentation
    • Design
    • Pressure
    • Temperature
    • Flow
    • Level
    • Vibration
    • Analyzer
    • Control Valve
    • Switch
    • Calibration
    • Erection & Commissioning
  • Interview
    • Instrumentation
    • Electrical
    • Electronics
    • Practical
  • Q&A
    • Instrumentation
    • Control System
    • Electrical
    • Electronics
    • Analog Electronics
    • Digital Electronics
    • Power Electronics
    • Microprocessor
  • Request
Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Inst Tools > Blog > Calibration > pH sensor calibration procedure

pH sensor calibration procedure

Last updated: April 25, 2017 11:07 am
Editorial Staff
Calibration
1 Comment
Share
3 Min Read
SHARE
A pH meter calibration is performed by measuring a series of reference standards, so-called pH buffers that have known and accurate pH values at different temperatures.
Choose the appropriate buffered standards that will bracket the expected values at the sampling locations. If the water body’s pH is unknown, then three standards are needed for the calibration: one close to seven, one at least two pH units below seven, and the other at least two pH units above seven. Instruments that will not accept three standards will need to be re-calibrated if the sample’s pH is outside the initial calibration range.

pH Sensor calibration procedure
pH Sensor calibration
Calibration Procedure:
1. Allow the buffered standards to equilibrate to the ambient temperature.
2. Fill calibration containers with the buffered standards so each standard will cover the pH probe and temperature sensor.
3. Remove probe from its storage container, rinse with deionized water, and remove excess water.
4. Select measurement mode. Immerse probe into the initial standard (e.g., pH 7 buffered solution).
5. Wait until the readings stabilize. If the reading does not change within 30 seconds, select calibration mode and then select “pH”. Enter the buffered standard value into instrument.
6. Remove probe from the initial standard, rinse with deionized water, and remove excess water.
7. Immerse probe into the second standard (e.g., pH 4 buffered solution). Repeat step 5.
8. Remove probe from the second standard, rinse with deionized water, and remove excess water. If instrument only accepts two standards, the calibration is complete. Go to step ‘II. Otherwise continue. .
9. Immerse probe in third buffered standard (e.g., pH 10 buffered solution) and repeat step 5.
10. Remove probe from the third standard, rinse with deionized water, and remove excess water.
11. Select measurement mode, if not already selected. To ensure that the initial calibration standard (e.g., pH 7) has not changed, immerse the probe into the initial standard. Wait for the readings to stabilize. The reading should read the initial standard value within the manufacturer’s specifications. If not, re-calibrate the instrument. If re-calibration does not help, the calibration range may be too great. Reduce calibration range by using standards that are closer together.
12. The calibration is complete. Rinse the probe with deionized water and store the probe according to manufacturer’s instructions.
13. Record the calibration information on the calibration log sheet.
Don't Miss Our Updates
Be the first to get exclusive content straight to your email.
We promise not to spam you. You can unsubscribe at any time.
Invalid email address
You've successfully subscribed !

Continue Reading

What is calibration?
RTD Calibration
Types of Calibration
How-to do Control Valve Calibration?
As-found and As-left Documentation during Calibration
Pressure Gauge Calibration according to Standard DKD-R-6-1
Share This Article
Facebook Whatsapp Whatsapp LinkedIn Copy Link
Share
1 Comment
  • Charles Palmer says:
    April 24, 2022 at 11:55 pm

    Very comprehensive and complete pH calibration procedure, thank you.
    Just one final step : the Buffer solutions need to be discarded after the procedure, not stored for further use.
    In many Industrial plants, the 4, 7 and 10pH buffers are used again, which is not a good idea .

    Reply

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Stay Connected

128.3kFollowersLike
69.1kFollowersFollow
210kSubscribersSubscribe
38kFollowersFollow

Categories

Explore More

Difference between Accuracy, Tolerance, Uncertainty, and Error
How to Calibrate the Eddy Current Conductivity Meter?
What is Reliability Centered Maintenance? (RCM)
Magnetostrictive Level Transmitter Calibration Procedure
Turbidity Sensor Calibration Procedure
Calibration of Measuring Instruments – Significance, Costs & Risks
The Principle of Dead Weight Pressure Tester
Calibrating Level Transmitter with Remote Seals

Keep Learning

Gas Detectors Bump Testing

What is Bump Testing ?

History of Measurement

History of Measurement

Calibration of Weight

Calibration of Weight using the ABBA Method

Fieldbus Flow Transmitter Configuration

Fieldbus Flow Transmitter Configuration

Instrumentation Engineer’s Calibration Mistakes

Common Mistakes in Dead Weight Tester

Common Mistakes to Avoid When Using Dead Weight Tester

Installation and Calibration of Pressure Transmitter

Installation and Calibration of Pressure Transmitter

Displacement Level Transmitter in situ calibration

Displacer (buoyancy) Level Transmitter Principle, Limitations, Design, Installation & Calibration

Learn More

Difference Between Modbus TCP IP and Profinet

Difference Between Modbus TCP IP and Profinet

RTD

Why 4 wire RTD Measurement Accuracy is better than 2 and 3 wire RTD?

Starting a Synchronous Motor

Starting a Synchronous Motor

6 Pieces of Essential Equipment For PCB Assembly

6 Pieces of Essential Equipment For PCB Assembly

Pressure Unit Conversion Practical Example

Pressure Unit Conversion Practical Example

How to Filter Digital and Analog Inputs in a PLC

How to Filter Digital and Analog Inputs in a PLC?

DDE Protocol

What is the DDE Protocol?

Hydraulic Systems Objective Questions

Hydraulic Systems Objective Questions

Menu

  • About
  • Privacy Policy
  • Copyright

Quick Links

  • Learn PLC
  • Helping Hand
  • Part Time Job

YouTube Subscribe

Follow US
All rights reserved. Reproduction in whole or in part without written permission is prohibited.
Welcome Back!

Sign in to your account

Username or Email Address
Password

Lost your password?