Conductivity Analyser Calibration SOP

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• Document control header (SOP ANA 004)
• Purpose, scope and references
• Safety, tools and prerequisites
• Numbered step by step procedure
• Acceptance criteria and records
• Approval block for sign off

1. Purpose

To keep conductivity readings accurate for water quality, blowdown and concentration control.

2. Scope

Contacting and inductive conductivity sensors with online transmitters.

3. References

• Analyser manual
• Standard solution certificate
• Site water chemistry limits

4. Responsibilities

• Instrument technician: carries out the work and records results.
• Instrument engineer or supervisor: reviews and approves the records.
• Operations: grants the permit, isolates the process and returns the equipment to service.

5. Safety Precautions

• Work only under a valid permit to work and follow the site isolation (lockout tagout) procedure.
• Wear the PPE required for the area: safety helmet, glasses, gloves and safety shoes as a minimum.
• In hazardous areas use certified or intrinsically safe test equipment, or obtain a gas free certificate and hot work permit.
• Inform the control room before starting, and before returning the instrument to service.
• Wear chemical gloves and eye protection when removing sensors from chemical lines.

6. Tools and Equipment

• Certified conductivity standard near the normal reading
• Clean beakers and rinse water
• Reference thermometer
• Cleaning solution as the manufacturer advises

7. Prerequisites

• Loop in manual or alarms inhibited as authorised.

8. Procedure

8.1 Remove and clean

1. Remove the sensor, rinse and clean deposits.
2. Inspect electrodes or toroid for damage.

8.2 Calibrate

1. Immerse in the standard at stable temperature without air bubbles.
2. Check the temperature reading against the reference thermometer.
3. Run the calibration so the analyser adjusts the cell constant to the standard value.

8.3 Verify

1. Rinse, then check a second standard if available.
2. Record cell constant, temperature coefficient and readings.

8.4 Return to service

1. Reinstall the sensor, confirm a sensible process reading and remove inhibits.

9. Acceptance Criteria

• Reading within tolerance of the standard (for example ± 2 % of reading).
• Cell constant change within the manufacturer limit.
• Temperature reading within ± 0.5 °C of reference.

10. Records

Related tools

This is a generic procedure. Adapt it to your site permit system, the manufacturer instructions and your quality system before use.

Frequently Asked Questions