Zeroflux Current Transducer (ZFCT)
Aims and Scope
Proficiency Tests (PT) give participants the opportunity to demonstrate technical competence, meet accreditation requirements, and gain confidence by comparing their results with those of other laboratories. They also provide independent insight into measurement performance, strengthen quality systems, and support risk management in line with ISO/IEC 17025:2017.
VSL organizes PTs under ISO/IEC 17043:2023 accreditation with the highest care, offering:
• A suitable traveling standard;
• A clear test protocol;
• An independent assessment report;
• Anonymous comparison of results;
• Optional metrological and quality management support.
Criteria of Participation
Participation is open to any laboratory performing optical instrument calibration, whether accredited to ISO/IEC 17025 or seeking accreditation.
Quantities to be Measured
10, 20, 50, 100, 200 and 500 A.
Travelling Standard
The instrument used for this PT will be a Zeroflux Current Transducer (ZFCT). This instrument is provided for measurements with a voltage supply for the ZFCT and a current shunt for readout.
Method and Equipment
Participants are advised to use their routine methods and equipment when performing measurements and calibrations. These should be carried out in accordance with the laboratory’s usual practices.
Instructions and Protocol
VSL will provide the protocol before shipping the instruments. Each participant will have at least three weeks to perform the measurements and submit the results. A report sheet will be provided for submitting the results.
Schedule
The PT will start on the date specified on our website.
Instruments will be delivered by courier to each participant. Each laboratory will have three weeks to perform the measurements and submit the results before the instruments will be sent to the next participant. The aim is to release the PT report no later than six weeks after the deadline for submitting the results by the participants. Detailed instructions and contact information will be provided.
Assigned Value
Reference values will be determined by VSL using traceable calibrated standards. These assigned values form the basis for evaluating each participant’s measurement results.
Performance Evaluation
The results will be evaluated using the normalized error (En-score).
Interpretation of the En-score is as follows:
|En| <= 1 Satisfactory performance
|En| > 1 Unsatisfactory performance
The final report presents results anonymously. Each laboratory can identify its own performance via a unique code. VSL guarantees full confidentiality and does not share individual data with third parties.
Deliverables
Upon completion of the PT, each participant will receive:
• A detailed report with anonymized results;
• An individual performance evaluation.
This report may serve as supporting evidence for audits and internal reviews.
Confidentiality Statement
VSL keeps all data regarding the performance of individual participants, or
groups of participants, strictly confidential. Data is accordingly protected and
stored in areas on networks with restricted access. The relationship between
results and the laboratories that submitted them will never be disclosed. Only
the laboratory is granted access to its performance through the assigned
code number.
Transport
VSL will handle and cover the shipment of instruments to all participating laboratories. Each participant is responsible for performing the calibration work within the agreed time frame and submitting their results using the provided report sheet, in accordance with the protocol. Detailed shipping instructions and tracking information will be provided, with all logistics fully managed by VSL.
Payment Terms
Payment in advance, at least one month before the start.
Failure to pay on time may result in exclusion from participation, without any right to refund or compensation.
Participants
This PT is open to 5-10 participants. If fewer than 5 laboratories register, VSL may cancel or postpone the PT. In such cases, all registered participants will be notified and offered alternative options.