Identify the exact machine and weighing positions
Use the machine serial, controller identity, head number and installed configuration. A generic record that cannot be tied to the actual instrument is weak evidence.
Direct answer
Calibration, verification and adjustment are different tasks and should be defined separately in the site's quality plan.
Calibration establishes the relationship between indicated value and a known reference under stated conditions. Routine verification checks whether the system remains within an agreed acceptance limit. Adjustment changes the instrument response. Finished-pack control is a separate production check and may use a checkweigher or sampling plan. The approved machine instructions, competent personnel and the site's legal and quality obligations determine the method.
| Term | Practical meaning | Evidence to retain |
|---|---|---|
| Zero check | Confirms that an unloaded weighing position returns to the expected zero condition | Date, operator, machine/head identity and result |
| Routine verification | Checks performance against a defined reference and acceptance limit without assuming an adjustment is required | Reference used, result, tolerance, environmental condition and action |
| Calibration | Establishes the relationship between the indication and known reference values under documented conditions | Procedure, references, results, uncertainty or traceability information where applicable |
| Adjustment | Changes the system so its response is brought back towards the required condition | Authorised change, before/after evidence, person responsible and follow-up verification |
| Finished-pack check | Measures the completed pack, including tare and any transfer losses after the weigher | Pack sequence, tare method, target, results, rejects and corrective action |
Verification plan
Define what is checked, by whom, with which reference and what happens after a failure.
Use suitable reference equipment
Reference weights and any independent check scale should be appropriate for the load, required decision and internal quality system. Keep their identification and status with the record.
Control the test condition
Record whether the machine is clean, isolated from product contact, stable, free from mechanical interference and in the approved test mode. Vibration, contact or residue can invalidate the result.
Use clear acceptance and escalation rules
State the permitted result, who may adjust the machine, when production must stop and how finished packs are assessed after corrective work.
Reconnect the check to production evidence
After verification or adjustment, review representative finished packs and the line sequence. A successful static check does not by itself prove the whole packing process.
UK packaged goods
Equipment suitability and production records belong to the packer's compliance system.
GOV.UK states that equipment used to weigh or measure packaged goods must be suitable, and that packers using the average system must keep records of sample-batch results. The multihead weigher setup, any independent checking equipment and the production sampling method should therefore be reviewed together. Local Trading Standards can advise on suitability for the specific business and product.
What records matter under an average system?
Keep the sample-batch results, the method used, the equipment identity, any corrective action and the period required by the applicable rules. The record must be clear enough to show how compliance was assessed.
Why is the multihead result not always the final pack result?
The finished pack also includes tare variation and anything lost, retained or added after the dose leaves the weigher. A downstream checkweigher or controlled sample method verifies the completed pack.
Buyer questions
Questions about multihead weigher calibration and verification.
How often should a multihead weigher be calibrated?
There is no responsible universal interval. Use the approved machine documentation, risk assessment, quality system, duty, product, environment, fault history and any legal or customer requirement to set the check and calibration plan.
Can an operator carry out the checks?
Operators may perform only the approved routine checks for which they are trained and authorised. Calibration, adjustment, repair or legal verification may require a technician, metrology specialist or other competent person.
Should every weighing head be checked?
The approved procedure should identify which heads, loads and system checks are required. A system-level result can hide a fault in one position, while head-level checks alone may not prove finished-pack performance.
What should happen after a failed verification?
Follow the site's documented escalation: stop or contain affected production where required, identify the cause, authorise any adjustment or repair, repeat the verification and assess product made since the last acceptable check.
Does a checkweigher replace calibration?
No. A checkweigher monitors finished packs; it does not replace the approved checks on the multihead weigher or reference equipment. The two systems provide different evidence.
What information helps Lancing review a weight-control issue?
Send the machine identity, target weights, recent verification records, ordered finished-pack data, product batch, feeder settings, fault history and any checkweigher or sample method used.
Verification review
Separate machine checks, finished-pack control and corrective action.
Send the installed configuration, product, targets and current weight evidence.
Discuss the verification planRelated guidance