Within the European Union, this field is regulated by the Measuring Instruments Directive (MID, 2014/32/EU), which defines the technical requirements for electrical energy meters and the procedures for their certification. The specific requirements for electrical energy meters—such as accuracy class, maximum permissible error, and permissible effect of disturbances—are defined in Annex MI-003 of the Directive.

In recent years, electronic smart meters have become dominant on the market. These meters enable bidirectional communication, real-time consumption monitoring, and integration into smart grids. This technological progress has required updates to standards and guidelines for type approval, as well as design examination. The latest standard, EN 50470-3:2022, specifies requirements for low-voltage electrical energy meters and refers to international IEC standards, such as IEC 62052-11:2020, which covers general requirements for accuracy, durability, and functionality, and IEC 62052-31:2022, which defines safety requirements. The standard defines the tests an electrical energy meter must undergo and the requirements it must met before being placed on the market.

WELMEC guides—particularly 7.2, 7.4, 8.x, and 11.x—together with EN 50470-3:2022 provide guidance on software integrity, security, and the interpretation of the MID. As a notified body, SIQ performs certification of active electrical energy meters under Module B (EU-type examination), Module D (conformity to type based on quality assurance of the production process), and Module H1 (conformity based on full quality assurance plus design examination).

The type approval process includes the preparation of technical documentation, prototype testing, and design assessment based on the review of technical documentation and test reports, as well as the assessment of the quality system for production of meters and their development. The new standards and WELMEC guides strengthen requirements for electrical safety, digital communications, cybersecurity, and robustness, while also enabling the integration of smart functionalities that improve grid efficiency and consumption transparency. For end users, the primary benefits are reliable measurements and fair billing.

The new EN 50470-3:2022 standard, in conjunction with applicable IEC standards and WELMEC guides, represents a significant step toward modern, safe, and accurate electrical energy meters. As a certification body, SIQ ensures compliance, safety, and support for manufacturers, in this wav enabling comprehensive control over measuring instruments and ensuring that even complex smart systems meet the highest standards of quality and safety while allowing efficient implementation on the European market.

Find out more about our calibration services.

The post Electrical Energy Meters: New Developments and Changes appeared first on SIQ.

For high-value, high-risk, or permanently installed systems, transporting equipment to an external laboratory can introduce unnecessary operational, financial, and technical risks.

SIQ on-site calibration services address these challenges directly — delivering accredited calibration at your premises, without compromising measurement integrity or traceability.

Why On-Site Calibration?

1️⃣ Reduced Operational Risk

Certain measuring systems are:

• High-mass or fixed installations (e.g., production lines, test benches)
• Sensitive to mechanical shock or environmental change
• Integrated into validated processes
• Classified as critical control points in regulated industries

Transport-related risks may include:

• Mechanical damage
• Performance drift due to transport stress
• Re-alignment or re-qualification requirements
• Extended downtime beyond maintenance windows

On-site calibration eliminates transportation risks entirely.

2️⃣ Significant Downtime Reduction

In capital-intensive industries, unplanned downtime may cost €5,000–€100,000+ per hour, depending on sector (automotive, pharmaceutical, energy).

On-site calibration enables:

• Execution during scheduled maintenance
• Parallel servicing of multiple systems
• Elimination of logistics delays
• Faster return to validated operational status

In practice, total interruption time is often reduced by 30–70% compared to traditional off-site calibration cycles.

3️⃣ Controlled Measurement Environment

When equipment cannot leave:

• Cleanrooms
• GMP-regulated production areas
• Secure laboratories
• Energy or safety-critical facilities

On-site calibration ensures:

• Environmental stability
• Preservation of validated conditions
• Compliance with internal and regulatory requirements
• No disruption of controlled access protocols

SIQ Special Accreditation for On-Site Calibration

SIQ performs calibration under an accredited scope in accordance with:

• ISO/IEC 17025 – General requirements for the competence of testing and calibration laboratories
• Full traceability to the SI system of units
• Documented uncertainty evaluation
• Validated procedures adapted for field conditions

Accredited on-site calibration guarantees:

• Equivalent technical validity to laboratory calibration
• Recognized measurement uncertainty statements
• Audit-ready documentation (ISO 9001, IATF 16949, GMP environments)
• International credibility and regulatory acceptance

Added Value Beyond Calibration: Partnership and Knowledge Exchange

Our clients consistently emphasize that the value of on-site calibration extends beyond technical compliance.

Direct interaction between SIQ metrology experts and client engineers enables:

• Immediate discussion of measurement challenges
• Practical optimization of measurement setups
• Clarification of uncertainty budgets and risk levels
• Exchange of operational experiences from different industries
• Identification of long-term improvement opportunities

This face-to-face collaboration strengthens technical understanding on both sides.

For many organizations, on-site calibration becomes not only a conformity requirement, but also a platform for professional dialogue and continuous improvement.

When On-Site Calibration Is the Optimal Choice

It is particularly beneficial when:

• Equipment mass or size limits transport feasibility
• Re-installation would require full system re-validation
• Systems are safety-critical or production-critical
• Transport introduces contamination or alignment risks
• Confidentiality constraints prevent equipment removal
• Measurement systems are permanently integrated into automation

Supporting Business Continuity with Accredited Expertise

By combining:

• Accredited metrological competence
• Controlled field procedures
• Risk mitigation
• Reduced downtime
• Direct technical collaboration

SIQ on-site calibration services provide measurable operational and compliance advantages.

If your measurement equipment cannot leave your facility — or simply should not — SIQ performs accredited calibration at your premises, ensuring both technical excellence and professional partnership.

Contact us to discuss your specific technical requirements and operational constraints.

Find out more.

The post On-Site Calibration: Minimizing Risk, Maximizing Operational Continuity appeared first on SIQ.

We’re pleased to announce that we have enhanced our calibration services to fully support ESD (Electrostatic Discharge) simulators, in alignment with the newly released IEC 61000-4-2 Edition 3 standard.

What’s new with Ed. 3?

• New calibration parameter (Ip2) – measurement of the second peak of the discharge current, reducing distortion caused by ringing and improving repeatability.
• Air discharge calibration requirements – including open-circuit voltage, addressing prior ambiguity in air discharge accuracy.
• Stricter measurement accuracy and test setup requirements – for greater consistency and reliability.

What SIQ now offers:

• Extended calibration scope for ESD simulators—including both contact and air discharge modes, in compliance with IEC 61000-4-2 Ed. 3.
• Precise measurements of peak current (Ip1), second-peak current (Ip2), current at standard checkpoints (30 ns, 60 ns), rise time, and open-circuit voltage—up to 30 kV.
• Enhanced traceability and alignment with the latest industry requirements, helping you maintain compliance and stay ahead.

Why does this matter to you?

• Improved accuracy – Ip2 ensures waveform fidelity is tightly controlled, reducing test variability.
• Broader coverage – with air discharge added to calibration, you gain confidence that the full range of discharge scenarios is properly validated.
• Trusted partner – SIQ remains committed to delivering the highest calibration standards in step with evolving regulations.

Curious about how we can support your EMC testing strategy or ensure your ESD equipment is fully compliant? Get in touch with our experts: info.metrology@siq.si

The post SIQ Strengthens ESD Simulator Calibration with IEC 61000-4-2 Edition 3 Capabilities appeared first on SIQ.

For many years, the Metrology department has been performing accredited calibrations of LCR meters. LCR meters are instruments used to measure the inductance, capacitance, and resistance of passive electronic components. In the past, most LCR meters operated up to a measurement frequency of approximately 1 MHz. However, the evolving needs of the industry have led to the development of a new generation of LCR meters capable of operating at frequencies exceeding several tens of MHz. Calibration laboratories are keeping pace with this technological advancement by developing accredited procedures that ensure traceable calibrations even for the most advanced instruments.

To calibrate an LCR meter, the values of the reference measurement standards used in the calibration must be known with high accuracy and traceability. To this end, we use reference resistors, capacitors, and inductors, which we used to send abroad for calibration. Calibration of reference capacitors at higher frequencies is particularly demanding and time-consuming, and as such, it is carried out by only a limited number of national metrology institutes worldwide. Due to long calibration lead times and the

risks associated with international transport, we decided to develop our own calibration procedure for reference capacitors.

We began the development of the new measurement procedure with a thorough review of relevant scientific literature. Several methods suitable for capacitor calibration were identified. We selected the one that offered the lowest measurement uncertainty and could be implemented using the measurement equipment available in our laboratory. The procedure employs a theoretical model of a reference capacitor, whose capacitance at higher frequencies depends on the values of nine elements that constitute the model. The values of six of these elements were determined directly from measurements and calculations at lower frequencies. The remaining three were derived indirectly from high-frequency measurements using a vector network analyser and computer simulations.

Since capacitance values derived from high-frequency measurements are subject to considerable uncertainty, we numerically simulated the values of the three unknown parameters and adjusted the model based on the high-frequency data. This step, not previously described in scientific literature, represents our original contribution to the field and enables a significant reduction in the overall uncertainty of the final capacitance value.

After its development, the procedure was validated through comparison with a foreign national metrology institute. This enabled us to obtain accreditation for the calibration of reference capacitors up to 30 MHz, with internationally comparable low measurement uncertainty.

With this newly developed procedure, we can now offer our clients accredited calibration of their reference capacitors and more efficiently provide calibration services for LCR meters.

The post Development of a Measurement Procedure for the Calibration of Reference Capacitors appeared first on SIQ.

The fifth edition of the IEC 61000-4-6 standard introduces specific requirements for decoupling clamps. It specifies that the decoupling must exceed 5 dB starting from 1 MHz, and more than 14 dB in a 50-ohm system. The SIQ decoupling clamps consistently exceed these thresholds, ensuring test validity and compliance with current basic standards.

Operating in the frequency range from 150 kHz to 80 MHz, the decoupling clamp is suitable for a wide range of conducted immunity testing applications. Whether testing information technology equipment, industrial devices, or consumer electronics, the decoupling clamps integrate seamlessly into your setup, ensuring reliable and reproducible test conditions.

Decoupling clamps are used for decoupling. The decoupling networks shall be used on all cables not selected for the test, but connected to the EUT or AEs, or both.

As part of our commitment to quality and technical excellence, SIQ developed the decoupling clamps entirely in-house, based on practical laboratory experience and the evolving demands of modern EMC testing.

The decoupling clamps are already in use in SIQ’s own ISO/IEC 17025-accredited EMC laboratory, where they contribute to reliable, repeatable, and compliant immunity tests.

In addition to their design for compliance with IEC 61000-4-6:2023, the decoupling clamp was developed in close collaboration with SIQ accredited calibration laboratory. This facility is staffed by a team of experts with extensive experience in RF and EMC measurements, ensuring each component meets the highest standards of precision and reliability. To support our customers throughout the lifecycle of their equipment, we also offer calibration services. Periodic calibration of decoupling clamp helps maintain measurement integrity, ensures continued compliance for both testing and R&D purposes, and contributes to more reliable, repeatable, and trustworthy results. This proactive approach ultimately supports product development, reinforces regulatory confidence, and enhances the overall quality of the final product.

SIQ offers decoupling clamps with openings of 15.5 mm and 25 mm.

Available for Purchase or Rental

Whether you are looking to equip your laboratory permanently or simply need clamps for a specific project or compliance campaign, SIQ offers flexible options. Both purchase and short-term rental agreements are available to meet your needs.

To learn more about SIQ decoupling clamps, request technical specifications, or receive a personalized offer, please contact our sales team via email safety@siq.si.

The post Decoupling Clamps for Reliable EMC Testing in Accordance with IEC 61000-4-6:2023 appeared first on SIQ.

In addition to the continuous internal development of metrological methods in support of the Slovenian economy to provide the traceability of measurements, our research team regularly applies to international European research projects.

Previously, national metrology institutes dealt with research in the field of metrology by themselves, with their own assets and personnel. Soon after 2000, the idea of combining research powers emerged. Thus, in 2007, the pilot project was launched called the European Metrology Research Programme (EMRP) iMERA+, where several NMIs joined forces in conducting research. Even then, we joined the research within the scope of the Power & Energy project, and our participation was very successful. Within the project, frequency-independent coaxial current shunts were developed, which are essential for measuring the quality of electrical power. The shunts made at SIQ achieved the best results. They are currently used in seven countries around the world. Since the experimental project was so successful, the EMRP research projects continued in the subsequent five years.
In this period, #SIQ participated in the following projects: SmartGrids, Harvesting, Electromagnetic Characterisation of Materials for Industrial Applications up to Microwave Frequencies (EMINDA), Quantum Standard for Sampled Electrical Measurements (Q-Wave), Advanced EMC Test Methods in Industrial Environments (EMC) and SmartGrids II.
No alt text provided for this image

Due to the success of the EMRP programme, the European Commission continued to co-finance metrology research with the seven-year European Metrology Programme for Innovation and Research (EMPIR). Within this programme, we also participated in three projects, namely the more accessible use of AC quantum voltage etalons (ACQ PRO), traceability routes for electrical power quality measurements (Trace PQM) and the development of metrology capacities in the field of RF and microwaves (RF Microwave). All three projects were launched to transfer knowledge between laboratories and, consequently, to bring the knowledge of small laboratories to a higher level.
A seven-year research project programme – European Partnership on Metrology (EPM) – is currently underway in the EU, which, after completion, will lead to the establishment of centres, the so-called European Metrology Networks (EMNs), where interested national metrology institutes (NMIs) and laboratories will combine knowledge and capacities in offering metrology solutions through a single entry point to all interested users. SIQ is already included in the Smart Grid Centre.
We were successful in the applications already in the first year of the EPM. This time, we will cooperate in developing metrology starting points for standardisation, namely in the projects Metrology for Digital Measuring Stations in the Electricity System (Digital-IT) and Metrology for Emerging EMC Standards (EMC-STD).

The post European research projects appeared first on SIQ.

1. Markus, you have been in the capacity of the TC-EM chair since May 2019. Can you tell us briefly what your key tasks are as the TC-EM chair and how much time it requires besides your regular work?
I am chairing the Technical Committee for Electricity and Magnetism (TC-EM) and as such the work is related to the implementation of the CIPM Mutual Recognition Arrangement (CIPM MRA) at the level of the regional metrology organisation EURAMET. With this mutual recognition arrangement, the National Metrology Institutes (NMIs) demonstrate the international equivalence of their measurement standards and their calibration and measurement certificates. The work is therefore to a large part related to the submission and review of national CMCs (Calibration and Measurement Capabilities) declared in the KCDB (Key Comparison Database) of the BIPM (Bureau International des Poids et Mesures) in Paris and things related to that, e.g. measurement comparisons. The KCDB has been modernized recently and features now a web-based interface. This is a major improvement compared to the previous system, which involved a lot of manual manipulation of individual files. But it is also changing the established way CMCs are dealt with and I am in the process of defining how CMCs should be submitted and reviewed in the future.

The TC-EM is also keeping an eye on the metrology research programs of the European Union and organizes workshops to foster the exchange of ideas that will be addressed within the next call for proposals. The current research program is soon coming to an end. With the new upcoming program, the European Union expects European metrology to become better coordinated, and as a consequence, European Metrology Networks (EMNs) are being formed. EMNs are supposed to have a strong stakeholder orientation to address big challenges in different sectors as energy, health, economy, etc. Many metrologists, who are in an EMN, might also be in one of the subcommittees of the TC-EM with thematically similar or even equal orientation. One of the challenges currently is therefore also to find out how the subcommittee structure of the TC-EM should adapt to these new groups in order to limit redundancies.

2. How important is from your point of view the decision made at the 26th meeting of the General Conference on Weights and Measures (CGPM) that all SI units shall be defined in terms of natural constants?
In a way it is just a further step in a continuous historical development during which the definitions of SI units have been changed in order to achieve more accurate and stable realizations of measurement standards. Having defined all SI units in terms of natural constants certainly is an important milestone, but it is also not the end. And my understanding is that the realizations of the new kilogram definition are still lacking the desired consistency. So, there is work ahead. I like the analogy I have read somewhere, where the significance of the new SI for the metrological system was compared to the reinforcement of the foundation of a house. The people upstairs don’t actually realize much, but for the structural stability of the house, the changes are essential.

3. What would be the major metrological challenge of our time, for example in fundamental science, industry, society and everyday life?
Obviously, metrology should not just end in itself. It should address challenges societies are faced with, i.e. it should help solve problems, ideally big problems. I agree with this, but I also see a danger that metrology is reduced to things that have an immediate impact. And there is a tendency in that direction with increasingly limited funds. But many innovations in the past were not planned. They occurred because scientists did things that were possible and not just things that were necessary. As of today, time is the most accurate measurement quantity. When the relevant techniques were developed, it was not foreseeable that this level of accuracy would ever be used. Nowadays atomic clocks in GPS satellites rely on this level of accuracy to provide precise positioning information. This is not only a challenge for metrology but for science in general. A way out for metrology would be to have even better coordination and cooperation among the different NMIs, especially at the European level. It seems to me that instead of having the same measurement standards again and again in each country, forces should be joined to have a much more diverse distribution of activities. But it seems that the national pride in having another reference standard for, e.g. time in operation is quite strong and not so easy to overcome.
Another challenge for metrology lies in digitalization and artificial intelligence with all the buzzwords related to it: Internet of things, Industry 4.0, machine learning, etc. How is it going to change metrology itself? What type of new metrological services might be needed? There are many open questions and I think nobody has a clear answer right now, but NMIs are taking the first steps to address these questions.

4. How is METAS as the Swiss National Metrology Institute funded, i.e. to what extent is it financed by the government, what is the proportion of market-based financing (calibration, industry projects), and what share is from nationally or internationally funded research work?
METAS is 50 to 60% self-financed. Self-financing consists of fees (services determined by regulations, such as verifications, type approvals, etc), compensation by the federal government for directly attributable services (operation of national measurement networks and laboratories for other federal agencies), industrial services (calibrations, industrial projects, etc) at about 30% each, and research funds at about 10%.

5. How has the coronavirus pandemic affected your work?
METAS has followed the instructions of the federal administration and reduced attendance at the institute to 30—40% together with other measures to force social distancing. But we are already in the process of relaxing these requirements again. It has slowed down things, in particular lab related work. On the other hand, it was and still is a good exercise in trying out home office and webconferencing. One or the other might have found out that virtual meetings are a viable alternative to face to face meetings. Although I believe personal interaction cannot and should not be totally substituted by virtual means.

6. In what way can metrology contribute to fighting pandemics such as we are witnessing today?
I don’t think I am the right person to answer this question. It is beyond my level of expertise to judge if a better metrological infrastructure in medicine would be helpful to fight a pandemic. Obviously, it is desirable to have reliable results in medical testing. As for the electrical field, contact tracing applications are currently being discussed. Radiofrequency and microwave metrology provide underpinning metrological services for communication devices, i.e. mobile phones, the applications run on.

7. What does Markus enjoy doing when he is not a metrologist?
As a metrologist, I am travelling quite frequently to meetings and workshops at interesting places, which is a privilege. I always try to add at least one day for my private pleasure instead of returning immediately to Switzerland. I like cultural things, music in particular, but also cooking, quality food and good company. When it comes to sports, I basically like anything that involves a ball. I used to play soccer, but this has become difficult because my knees are not in good shape anymore.

The post Interview: Dr. Markus Zeier appeared first on SIQ.