Electronic Weighing scale calibration

[abdul42550]

Hi
Scenario..... Customer audited and NC raised that you have to calibrate your weighing scale from outside NABL accredited agency, and measuring tape and scale can be done in house calibration with master but weighing scale can not do inhouse calibration? I have 400 nos. weighing scale used in process which cost is very high if I go for outside calibration. I said to auditor could I purchase the Master of Weighing scale and calibrate inhouse. Auditor replied that Weighing scale must be calibrated from outside NABL accredited agency. However you can calibrate the other instrument like scale, tape, vernier etc. inhouse.

Question - May I do In house calibration from weight Master? Which standard I can refer to satisfy the auditor that we can do inhouse calibration of Weighing scale.

 

[Jen Kirley]

Hello abdul42550,

As a Supplier Quality Engineer I commiserate with you when receiving these types of customer requirements. I do also remember auditing an organization whose conveyor scales were getting their short term checks (daily/weekly, I cannot remember) with kettlebell weights purchased from a department store. I found myself needing to go into the entire speech about how the standard requires traceability in calibration/verification... the auditees behaved as though they were hearing this for the first time.

That memory makes me feel sympathetic to your customer. In any case, the customer can require traceability as per ISO 9001:2015 (or whatever standard, you did not say which applies to you) as well as an additional requirement if they state it in their contract with your organization. Have you reviewed that recently?

I hope this helps.

 

[jay747]

Try to understand your auditor requirement and convince him with a weighing scale verification plan for the whole range of equipment with. We had the same comment from an auditor once and we implemented a daily verification on all the weighing scales using calibration weights (which are verified annually from an NABL accredited agency) along whole range combined with the annual Inhouse calibration.

You can also try including eccentricity test in your calibration procedure.

 

[dwperron]

Hi
Scenario..... Customer audited and NC raised that you have to calibrate your weighing scale from outside NABL accredited agency, and measuring tape and scale can be done in house calibration with master but weighing scale can not do inhouse calibration? I have 400 nos. weighing scale used in process which cost is very high if I go for outside calibration. I said to auditor could I purchase the Master of Weighing scale and calibrate inhouse. Auditor replied that Weighing scale must be calibrated from outside NABL accredited agency. However you can calibrate the other instrument like scale, tape, vernier etc. inhouse.

Question - May I do In house calibration from weight Master? Which standard I can refer to satisfy the auditor that we can do inhouse calibration of Weighing scale.

A few questions to help us understand your position.
You say that your customer audited you and said that your scale must receive an NABL accredited calibration.
What was the actual NC that the auditor cited? Where was that requirement?
Did your customer require this in their contract with you?
Is your organization accredited to ISO 17025? If so, for testing or calibration?
Does the other equipment that you calibrate internally need ISO 17025 accredited calibrations?

 

[BradM]

Dwperron covered all the questions I have.

So just in general, I'm a bit perplexed that you were told you can't calibrate your own weighing scale. Like any other instrument, if you have competency, a valid procedure and suitable standards, barring some contractual obligation or industry requirement, you should be able to check your own scales.