Understand the responsibility and technical evidence behind the mark

CE marking indicates that the manufacturer takes responsibility for the product's conformity with the applicable legal requirements. Although people often ask for a “CE certificate,” the process does not consist of a single certificate issued by the same organisation for every product. Product scope, conformity assessment, technical documentation and the declaration of conformity must be considered together.

CE should not be treated simply as a testing laboratory's label. Industrial standards can help evaluate the technical solution, while the applicable legislation determines the obligations. The right to affix the mark depends on completing the required procedures.

Which products require CE marking?

CE marking applies to products covered by legislation that specifically requires it. Electrical equipment, machinery, toys and medical devices may fall under different rules. CE marking does not belong on every product. It must not be added for marketing purposes to a product for which the legislation does not provide for it.

More than one legal act may apply. For automation equipment, electrical safety, electromagnetic compatibility, restrictions on certain hazardous substances and wireless communication requirements must be considered as relevant. For the Turkish market, also check the applicable national technical regulations; quoting an EU directive's name alone is insufficient.

Does operating at 24 V remove the CE requirement?

Subject to its scope and exclusions, the Low Voltage Directive 2014/35/EU (LVD) concerns electrical equipment designed for use at 50–1,000 V AC or 75–1,500 V DC. A PLC module operating solely at 24 V DC may be below those limits, but that does not exempt it from every CE obligation; other legislation may apply.

Assessment therefore goes beyond the supply rating. Consider the product's function, connections, operating environment and relevant exclusions. Being outside the LVD's scope does not remove the need to evaluate product safety.

Why is following a standard insufficient on its own?

IEC standards and EN standards should not be assumed to have identical legal roles. Harmonised standards whose references are published in the EU Official Journal under the relevant legislation can provide a presumption of conformity for the requirements they cover. Check the edition, scope and any restrictions.

Using harmonised standards is generally voluntary. An alternative technical solution must still provide evidence that the mandatory legal requirements are met. Printing a standard number in a catalogue does not replace conformity assessment.

The practical sequence for CE marking

Define the product and its intended use. Establish the exact model, function, supply, intended users and operating environment. Identify the applicable legislation and assessment procedure for each relevant act. Products that look alike may have different obligations because their intended uses differ.

Assess the risks and assemble the evidence. Technical documentation brings together the product description, design and circuit information, critical components, applied standards, necessary test results, risk assessment, labels and instructions. Organise it to explain how the requirements applicable to the product have been met.

Establish whether third-party involvement is required. Some procedures allow assessment under the manufacturer's own responsibility; certain products and procedures require a notified body. Check its NANDO entry for the relevant legislation and assessment tasks. A testing laboratory is not automatically a notified body. The LVD does not require notified-body involvement in conformity assessment.

Draw up the declaration of conformity. The EU Declaration of Conformity commonly encountered with automation products identifies the manufacturer, product, applicable legislation, standards, any required body details and authorised signature. Prepare it after assessment is complete. Use the title and format required by the legislation; for example, the current Machinery Directive uses an EC declaration.

Affix the mark and maintain the records. CE marking must be visible, legible and indelible, with its proportions preserved. Unless the product rules provide otherwise, the minimum height is 5 mm. Keep the technical documentation and declaration for the legally required period and update them when relevant changes occur.

Components and the finished automation system

Combining CE-marked parts does not automatically complete assessment of the finished machine. For example, the wiring and installation conditions in a variable-frequency drive's instructions must be considered in the final assembly. EMC filters and EMC emissions may form part of that evaluation; fitting a filter alone does not establish conformity of the whole system.

As of 17 October 2026, EU machinery legislation is in transition. The existing Machinery Directive 2006/42/EC applies, while the general application date of Machinery Regulation (EU) 2023/1230 is 20 January 2027. The machine's date of placing on the market and the relevant transitional provisions determine the applicable regime.

Is UL the American equivalent?

There is no single US equivalent to CE marking across all products. Certain workplace equipment covered by OSHA requirements may need NRTL testing and certification. Read UL, ETL or CSA certification marks against the applicable US standards and recognition scope. CE marking alone does not satisfy these NRTL requirements.

Related standards and regulatory topics

RoHS addresses substance restrictions, while EN 61000 covers electromagnetic compatibility topics. EN 61010 concerns measurement and control equipment safety, IEC 61800 concerns drives, and IEC 60947 concerns switchgear and controlgear. These are useful starting points; select the exact standard and edition for the product's scope.

Related categories to assess in the application

For power supplies, variable-frequency drives, contactors, fuses and encoders, consider the product's role, electrical ratings and installation conditions together. Their documentation can contribute to the technical file according to the function each product performs in the completed assembly.