QUICK ANSWER
What to Know First
Record the make, model, serial number, gauge head, controller, cable and settings. State the working range, gas, required test points and acceptance or documentation need. Preserve as-found information, review safe handling and contamination, and agree the work before shipment or adjustment.
OVERVIEW
The Technical Context
Calibration establishes a relationship between reference values and an instrument's indications under stated conditions. It differs from adjustment, repair and confirmation against an acceptance requirement.
Preparation makes that work representative of how the equipment is used. The head, cable, controller, mounting, gas and configuration can form part of the result. An unidentified sensor alone may not define the full measurement requirement.
- Identify the full measurement chain.
- Define points, gas, units and documentation.
- Preserve as-found settings and history.
- Arrange safe handling before shipment.
ENGINEERING GUIDANCE
Separate Calibration, Adjustment and Repair
| Objective | Purpose | What to agree |
|---|---|---|
| Calibration | Relates indications to reference values under defined conditions. | Points, configuration, uncertainty/documentation and conditions |
| Adjustment | Changes the indication or response. | Permission, method and evidence before/after the change |
| Repair | Addresses an identified fault or damage. | Feasibility, parts, scope and post-work checks |
| Verification | Confirms whether a stated requirement is met. | Acceptance rule, relevant evidence and decision responsibility |
ENGINEERING GUIDANCE
Identify the Complete Measurement Chain
- Manufacturer, complete model, revision and serial number
- Gauge head, controller/display and power supply
- Associated cable type, length, outputs and software/configuration
- Connection, normal mounting/orientation and operating units
- Manual, nameplate photographs and previous calibration or service records
ENGINEERING GUIDANCE
Define the Required Pressure Points and Conditions
Provide the normal working band and the points important to the process or quality decision. State the pressure unit, gas or mixture, reference conditions and whether outputs or set-points also need evaluation.
ISO 3567:2026 describes direct-comparison vacuum gauge calibration conditions, including the measurement chain. Referencing a standard does not establish a provider's accreditation or achievable range. Agree the actual scope and documentation in the proposal.
ENGINEERING GUIDANCE
Preserve As-Found Evidence
Record current settings, correction factors, fault messages, observed deviations and the reason calibration is requested. If the issue is an unstable reading, retain a time trend and process conditions rather than only an isolated screenshot.
Do not reset, trim or adjust the gauge merely to make the reading look plausible before the scope is agreed. Such a change can remove useful evidence of the original condition. Agree whether adjustment is authorized and how the before/after information will be recorded.
ENGINEERING GUIDANCE
Disclose Exposure and Arrange Safe Handling
Describe gases, oils, vapours, cleaning chemicals, particles and any potentially hazardous contamination. Obtain the receiving provider's handling/return instructions and disclose the process history before transport.
Cleaning is sensor and material specific. Do not apply a generic solvent or disassemble a delicate sensing element without the exact approved instructions. Protect ports and fragile parts, and use suitable packaging after the equipment is made safe.
ENGINEERING GUIDANCE
Agree the Required Documentation and Return Configuration
State whether the need is measured data, a comparison report, a certificate, a stated uncertainty, a traceability requirement or a pass/fail decision against a defined rule. These are distinct deliverables and must be confirmed before work.
Check equipment identification, configuration, gas, points, conditions, result and any adjustment in the returned record. Restore the agreed installation and settings. Choose the next calibration interval from duty, drift history, manufacturer guidance and the measurement-control plan rather than a universal calendar rule.
PRACTICAL WORKSHEET
Gauge Calibration Preparation Checklist
Send these details before arranging shipment or approving work.
Equipment
- Make, model, revision and serial
- Head, controller, cable and accessories
- Manual, connector and mounting details
Measurement requirement
- Working band and important test points
- Units, gas and output/set-point needs
- Acceptance rule and document requirements
History
- Current settings and correction factors
- Symptoms, previous results and service work
- As-found information and adjustment permission
Handling
- Process exposure/contamination disclosure
- Provider's receiving and packaging instructions
- Protected ports, safe accessories and return setup
PRIMARY REFERENCES
Technical Sources and Further Reading
These references support the general technical explanation. Always use the current instructions and approved procedure for the exact equipment and task.
