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On this page, you will find an overview of all topics related to CE marking. From an initial introduction to specific guidelines and practical tools.

 

 

Do you have questions about CE marking? Or would you like support or advisory services, please contact us via richard@euronorm.net or view our advisory services.

 

Author: Drs. Richard Winter

 

On this page, you will find an overview of the most important topics regarding NEN 3140: from the designation of personnel to the inspection of electrical installations and appliances, requirements for safe working, and several handy tools you can use.

 

Do you have questions or are you looking for practical advice or support? Contact us at richard@euronorm.net.

 

Author: Drs. Richard Winter

 

Legislation mandates periodic inspection of work equipment that may pose a hazard due to factors such as wear or aging.

Inspection of electrical equipment

The NEN 3140 inspection consists of a visual inspection and several measurements. Electrical equipment must be periodically inspected by a Sufficiently Instructed Person (SIP) with the appropriate knowledge and measuring equipment.

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Inspection of ladders, stepladders, and rolling scaffolds

Climbing equipment such as ladders, stepladders, and rolling scaffolds must be periodically inspected in accordance with NEN 2484 or EN 131.

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Inspection of lifting equipment

Lifting equipment such as slings, chains, and steel wire rope slings must be inspected at least once a year by an expert (Working Conditions Decree, Art. 7.20).

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Inspection of fall protection equipment

Safety harnesses, lanyards, and shock absorbers must be periodically inspected. Always start by determining the year of manufacture.

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Inspection of warehouse racks

NPR 5055 is used for the inspection of warehouse racks.

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Inspection of emergency stop devices

Emergency stop devices must be subject to verifiable periodic checks.

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Inspection labels for inspections

After an inspection, it is standard practice to attach an inspection label to the work equipment. Our vinyl inspection labels (25 mm) are suitable for all common work equipment.

View inspection labels →

If you have a question or are looking for a course in this field, take a look at our webshop. If you are looking for some practical support, please feel free to contact us.

Author: Drs. Richard Winter

Over the past 35 years, we have gained extensive experience in artisanal consulting and providing courses on CE marking, NEN 3140, NEN 3840, as well as conducting risk analyses on all types and sizes of machines, production lines, pump plates, tank farms, etc. With this experience, we have also been able to develop a series of practical (online) courses.

Often, our work consists of a combination of consulting, because everything has to be correct, and then setting up one or more (online) courses and placing them behind a company login.

Below are some examples of our work to give you an idea of what we do.

 

Example Client 1. NEN 3140 and NEN 3840 online for IV, WV, VP

Due to the nature of the work, it proved very difficult for this client to gather groups for an old-fashioned 'classroom' course. Employees worked in shifts and at locations inaccessible by car. So it made sense to set up 'something' online and a single 'classroom course' for new employees.

Example client 2: NEN 3140 WV, VP and VOP and 8 toolboxes

This client has employees stationed at very different locations, and here too it proved difficult to gather groups. Behind the login, 3 courses (WV, VP and VOP NEN 3140) and a total of 8 toolboxes have been placed.

 

Example client 3: Gas measurement in confined spaces

For another client, we conducted a compliance investigation at a tank farm, and there was also a need to provide instruction for 'manhole watchers' and also instruction on how to perform 'gas measurements' before entering a confined space.

Example client 4: Inspection of work equipment (3 standard course modules)

For this client, the wish was to place 3 inspection courses behind the company login for approx. 6 people. The cost of this company login is the same as buying these 3 courses for 6 people in the shop.

 

Example client 5: CE-marking with dossier formation

For this client, we set up an English-language online course on CE-marking and also drafted a legal framework.

 

How does the company login work?

To ensure smooth invitation of participants, we always compile a PDF with information that the client can send to its participants.

 

Certificates automatically in your mailbox!

After a participant has completed the course, he/she must take a test, and upon passing the test, a certificate will follow. These certificates are forwarded to the email address of someone at the client.

 

Classroom or online?

Of course, we also give all courses in a classroom setting. Based on our experience, we have summarized the choice in the table below.

If you are also considering consulting, please contact us.

Richard Winter / richard@euronorm.net / 06 27262529

 

The new Machinery Regulation also makes digital user manuals possible and even recommended.

We have already created a number of user manuals in video format, and I must say, to our complete satisfaction. It has, of course, long been the case that when you encounter a problem, you search on YouTube rather than in a thick user manual. And, indeed, on YouTube, you often found someone who had put together some video where your problem immediately became clear. How great is that?

If you are also interested in a digital user manual for your product, please contact us.

 

Philip Warneke

 

 

 

 

For a Sufficiently Instructed Person (SIP) NEN 3140, distribution boards or, for example, control cabinets are accessible, but they must be touch-safe, meaning IP 2x. If this is not the case and you are not going to make them touch-safe, then the SIP is not allowed to work on them.

These protection classes are often relevant for NEN 3140 and also for ATEX implementations. If you would like support, please contact us.

Below is an overview of the IP protection classes.

Whether you need to engage a Notified Body (NoBo) depends on the Directive or Regulation applicable to your product. A rule of thumb is that if it's a high-risk product such as a medical device or, for example, a product for use in potentially explosive atmospheres, the likelihood increases. Also, for pressure equipment, especially with gas, and particularly if it's a hazardous gas, you'll likely need one. We provide some explanation in a short video. And, if you scroll down further, we offer more explanation for several Directives/Regulations.

A NoBo is a conformity assessment body notified to the European Commission. An overview of NoBos can be found in the NANDO database of the European Commission. Whether you are obliged to engage a NoBo depends on the risks of the product. For a hazardous product, it is highly likely that engaging a NoBo is mandatory. For instance, the Machinery Regulation includes a list of 'dangerous machinery,' consisting of Part A and Part B. If the product is in Part A, a NoBo must be engaged; if it's in Part B, it may be engaged but is not mandatory. For the EMC Directive, Low Voltage Directive, and also the RED Directive, a NoBo does not always need to be engaged, provided that the supporting evidence (=tests) have been carried out based on certain (harmonized) standards. You can often perform these tests yourself or outsource them to a testing laboratory (not a NoBo). In short, engaging a NoBo is mandatory for high-risk products such as medical devices, products for use in potentially explosive atmospheres, and certain dangerous machinery. But only from a certain category. That may be so, but how do I find out if I need to engage a NoBo? Determine the Directives applicable to your product. Look in those Directive(s) for something like: 'Conformity Assessment'.

• Check if you find any indications there that you can do it yourself or not.
• If engaging a NoBo is not mandatory, you can do it yourself, and you can find supporting documents and e-learnings on our site.
• If you do need to engage a NoBo, you can find them in the NANDO Database of the European Commission.

We summarize the conditions for engaging a NoBo per Directive. We don't have them in Dutch yet, but I think the explanation is clear.

Machinery Regulation (valid from 2027)

So if your product is in Part A, you must call a NoBo. Below you can see which products fall under Part A. As you might expect, there is also a 'Part B', these are also higher-risk products, but for the products mentioned there, the manufacturer may assess conformity themselves.

PART A - Machinery RegulationCategories of machinery and related products for which a procedure as referred to in Article 25, paragraph 2, must be followed Removable mechanical transmission systems, including their guards. Guards for removable mechanical transmission systems. Vehicle lifting equipment. Portable cartridge-operated fastening tools and other impact machines. Safety components with fully or partially self-evolving behavior using machine learning methods that ensure safety functions. Machinery with integrated systems, not independently placed on the market, with fully or partially self-evolving behavior using machine learning methods that ensure safety functions, solely with regard to those systems.

Current Machinery Directive

In the current Machinery Directive, the obligation to engage a NoBo is shown in the diagram below.

EMC Directive

For electronics that are self-designed or being designed, an EMC test may be necessary to demonstrate conformity with this Directive, as there would be no paper evidence otherwise. However, such tests do not need to be performed by a Notified Body but can also be conducted in-house, provided that harmonized standards are used for the tests.

When performing EMC tests, ensure that a report is produced which can later demonstrate that the immunity and emission requirements of the EMC Directive, whose limit values are specified in certain standards associated with the EMC Directive, have been met.

Low Voltage Directive

For the Low Voltage Directive, similar principles apply as for the EMC Directive. Here too, you must have evidence of compliance, and if it involves purchased components, check the documentation. If it's your own design, you often lack this burden of proof, so a test will need to be performed. Use harmonized standards falling under the Low Voltage Directive for this. You can perform these tests yourself or outsource them.

ATEX 114 Directive

If your product is intended for use in potentially explosive atmospheres, it will fall under ATEX 114. If it is a mechanical product (i.e., not electrical) and suitable for Zone 0, you must engage a NoBo. The same applies if it is an electrical product suitable for Zone 0 and/or Zone 1.

And, if that is not the case, you do not need to engage a Notified Body. Of course, you may, but it is not mandatory based on the Directive.

If you need to engage a Notified Body, request multiple quotes and also check which tests are included in the quote, as we often see that more tests are 'quoted' than necessary.

 

Author: Drs. Richard Winter

If you have any questions about this, please contact us.

 

 

Many products are partly completed systems that are built into something else to perform their function. In such cases, it appears at first glance to be an 'incomplete machine or product'; it is not yet finished but is only part of the whole. In CE marking, however, we only encounter the term 'partly completed machinery' in the Machinery Regulation. The product must therefore first fall within the scope of this Directive, and only then can it be assessed whether or not it is 'partly completed machinery'. In the EMC Directive, the Low Voltage Directive, the Radio Equipment Directive, and, for example, the PED, we do not have the term 'partly completed machinery'.

The definition of partly completed machinery, according to Article 2(g) of the Machinery Regulation, states:

"partly completed machinery": an assembly which is almost machinery but which cannot in itself perform a specific application. A drive system, for example, is partly completed machinery. Partly completed machinery is only intended to be incorporated into or assembled with other machinery or other partly completed machinery or equipment, thereby forming machinery to which this Directive applies;

Examples of this include an electric motor plus an attached gearbox, an internal combustion engine, or a high-voltage motor.

"An assembly that is almost machinery" means that partly completed machinery is a product equivalent to machinery in the strict sense of Article 1(1)(a), i.e., 'an assembly of interconnected parts or components, at least one of which moves, but which lacks certain elements to perform its specific application.

Partly completed machinery must therefore be incorporated into other (partly completed) machinery, thereby enabling its specific application to be performed. This assembly does not refer to the mounting of a drive system on a machine supplied without a drive system (assembly), but is intended by the manufacturer to be equipped with a drive system. This assembly also does not refer to connection at the place of use or to power or drive sources. A machine that needs to be assembled by a user from separate parts is a complete machine.

The question of whether a machine can independently perform a so-called "specific application" is the most important criterion for classifying a machine as partly completed machinery. Machines must be usable for a specific application. Typical machine applications include, for example, the processing, handling, or packaging of materials, or the movement of materials, objects, or persons. A common misinterpretation of the term 'specific application' is the frequently heard statement, "Our machine can only fulfill its function when it is installed in the production line." Take, for example, a machine that comes with its own control system but needs to be placed between other machines. On its own, the machine cannot perform its intended function.  Nevertheless, it is a complete machine because, after connecting the power supply and applying the control signals, the machine can perform its own 'specific application' within the production line.

 

It is also sometimes assumed that machines sold without protective measures due to integration into a line are partly completed machines. Given the foregoing, a machine that can perform its specific application by itself but only lacks the necessary protective equipment or safety components is not considered partly completed machinery.

What we often see is that when assembling machine lines, partly completed machines are incorrectly supplied, when they should actually have been completed. If a machine can operate independently but is intended to be assembled (see conveyor belt example) in a line configuration, then it is expected that this machine will be supplied as a complete machine. This means with CE marking and an II 1.a declaration.

When such a complete machine is nevertheless placed on the market as partly completed machinery, the manufacturer deliberately shifts the responsibility to the machine line builder. 

 

An example:

A conveyor belt machine is placed between two processing machines. The manufacturer of the conveyor belt machine supplies the machine as partly completed machinery with an II 1.b declaration. This means that this conveyor belt machine is not CE-compliant and therefore does not have CE marking. As the machine line builder, you must then ensure not only that the assembly with the other machine (the transitions) but also the conveyor belt itself is CE-compliant. In other words, as the machine line builder, you must perform the full risk assessment for the conveyor belt machine in addition to the overall line configuration. And if residual risks that are unacceptable arise from this, you must adjust and resolve them yourself. Whereas, if you had purchased a CE-marked conveyor belt machine, you would primarily need to ensure the CE compliance of the assembly with the conveyor belt machine and the overall line configuration. All non-CE compliance related aspects that should have been covered under the CE marking of the conveyor machine can be referred back to the relevant manufacturer!

 

Author: Philip Warneke

We build machines and wonder what the most important changes are with the arrival of the new Machinery Regulation. Or is it old wine in new bottles?

Yes and no, in January 2027 the Machinery Directive will be replaced by the Machinery Regulation (EU) 2023/1230. Because projects often have a long lead time, it has been decided to already include the requirements of the new Machinery Regulation in the Compliance policy. 

 

The Machinery Regulation may apply if the product contains rotating, moving parts and is driven by electrical, hydraulic or, for example, pneumatic energy. 

But, beware, because lifting and hoisting tools such as a lifting sling, lifting eyes or a steel wire rope sling also fall within the scope of this regulation. Therefore, for each product, it must be carefully assessed whether it falls within the scope of this regulation. 

If it has been determined that the product falls under the scope of the Machinery Regulation, it must still be checked whether your product is not on the list of exceptions. For example, if it is a trailer or if the product is intended for use at a fairground or if it concerns a firearm for use in war zones, the product does not fall under the Machinery Regulation. It is therefore very important to check whether it does not fall under the exceptions, because then the Machinery Regulation does not apply.

Below we have included the literal legal text of the scope and the exceptions.

 

Scope (Article 2.1)

This Regulation applies to machinery and the following related products:

1. interchangeable equipment;
2. safety components;
3. lifting accessories;
4. chains, ropes and webbing;
5. removable mechanical transmission devices.

This Regulation also applies to partly completed machinery.

For the purposes of this Regulation, machinery, the related products referred to in the first paragraph and partly completed machinery are together referred to as "products falling within the scope of this Regulation" or "products falling within the scope of this Regulation".

Overview of the changes

 

 

Read more

 

In a short course, we have explained the most important changes.

Drs. Richard Winter

If you need support in implementing the changes, please contact us or send an email to richard@euronorm.net 

 

The inspection of electrical equipment consists of a visual check and several measurements that must be performed with a suitable measuring instrument. You can find the frequency, and whether this should be done annually or otherwise, in a separate appendix to the NEN 3140 standard. In practice, with few exceptions, the frequency is almost always once per year.

Further explanation can be found here:

• What does the visual check consist of?
• Which measurements must you perform?
• How do you measure the protective conductor?
• How do you measure the insulation resistance?
• How do you measure the leakage current?
• How do you measure leakage current for PCs, etc.?
• Who is authorized to perform these inspections?
• Are you allowed to inspect your own equipment?
• Can you test fully plastic-housed appliances?
• How do you inspect a portable distribution board?
• What are the differences in requirements between the Netherlands and Germany?
• How do you check a residual current device (RCD)?
• How do you inspect cable reels and extension cords?
• How do you inspect a portable distribution board?
• How do you make an adapter plug for testing 3-phase devices?
• Tips for purchasing measuring instruments
• After a NEN 3140 inspection, the device no longer works; how is that possible?
• Is NEN 3140 training mandatory?
• Is calibration mandatory according to NEN 3140?

We have also developed a practical online course in which we explain this inspection in a practical way. The course also includes teaching materials and an inspection checklist in WORD format. The course concludes with a certificate.

 

Author: Drs. Richard Winter

 

 

< Back

Chain slings must also be visually inspected at least annually. Chain slings is a collective term that covers various lifting tools such as 2-leg slings, 4-leg slings, eye bolts, master links, couplings, shackles, and hooks.

The visual inspection of chain slings consists of:
- Is the CE declaration (IIA declaration) present?
- Do the details stated on it match the chain sling?
- Is the capacity indication on the tool legible?
- Is the identification on the tool still legible?
- Is the tool not deformed?
- Is the tool not damaged?
- Is the tool not worn?
- Are the various connecting elements still in good condition?
- Have repairs been expertly carried out and is there proof of this?
- Is the safety latch present on the hook?
- Is the tool not affected by corrosion?
- Are all moving parts still functional?
- Has any prescribed testing been carried out in a timely manner?

Author: René Bak

 

Climbing equipment such as ladders, stairs, and rolling scaffolding must also be inspected periodically. First, you need to determine whether these materials comply with certain standards. For example, ladders and stairs must comply with NEN 2484, EN 131, or EN 1147 (ladders for the fire department), and rolling scaffolding must comply with EN 1004. Often, this information is indicated on a sticker on one of the components. Check carefully if you can determine this, because otherwise, the inspection will stop, and you will unfortunately have to reject the equipment. After all, you cannot determine whether it was manufactured according to the requirements.

With new climbing equipment, you can see that various manufacturers laser the standard designation into the material, which remains much more visible than a sticker. Below, you can see this on a ladder used by the fire department that complies with EN 1147, and below that, an image of a ladder with the necessary markings; this also meets the requirement.

Once you have determined that it complies with the relevant standard, you must give the climbing equipment its own code. This can be done, for example, by providing the equipment with a unique number, possibly combined with a letter.

Then, create a list of the climbing equipment you are going to inspect. On that list, also include the number you assigned to it and provide a description such as: "two-part ladder with 12 rungs per part." This will make it easier to find it the next time you perform the inspection.

If this is in order, check all parts for cracks, dents, corrosion, bends, damage, or missing parts. Also, pay attention to contamination of, for example, the rungs or steps by oil, paint, grease, and other dirt that can cause a slipping hazard.

1. Also check all connections, rivet connections, and weld seams between the vertical and horizontal parts (rungs and stiles / steps and stringers).
2. Excessive play or deformation can also lead to rejection.
3. Check for anti-slip profiles and wear.
4. Also check whether the rubber or plastic feet have sufficient anti-slip properties.

Using a checklist as shown below, you go through the inspection item by item and determine whether it is approved or rejected. The inspection list can also be found in Downloads.

Further information about fire department ladders EN 1147 can be found here.

The standard designation is missing, what should I do?

We have developed an e-learning module in which we teach you how to perform these inspections in a number of videos; the course material and inspection lists are, of course, included and covered point by point. You conclude the course with an (online) test, and a certificate follows.

Author: Drs. Richard Winter

 

Regarding electrical safety, under the Working Conditions Act (ARBO), the employer is responsible for ensuring that electrical installations, equipment, and appliances are safe to use. The employer is also responsible for providing information and instruction to their employees. They must be aware of the applicable safety regulations.

The general requirements formulated in the Dutch Working Conditions Act (ARBO) have been further elaborated in the NEN 3140 standard (Low-voltage installations; Regulations for safe work, inspection, and maintenance). This standard specifies provisions to prevent electrocution or short circuits during work. If you comply with the provisions of NEN 3140, you also meet the requirements of the Dutch Working Conditions Act (ARBO) regarding electrical safety.


NEN 3140 basically consists of three topics:
1. Electrical installations must be safe to use
2. Power tools must be safe to use and
3. Persons working on and around electrical installations must be instructed in safety


Ad. 1. Electrical installations
To ensure the safe use of electrical installations as much as possible, the standard stipulates that electrical installations must be inspected periodically. The inspection consists of a visual inspection and an inspection by measurement and testing. An inspection may be carried out by at least one 'Competent person' , this person has knowledge of electrical engineering at least at a lower level of education in energy technology and has knowledge of NEN 3140, NEN 1010 and any additional standards relating to carrying out an inspection.


Ad. 2. Electrical appliances
To ensure the safe use of electrical equipment, extension cords, etc., NEN 3140 requires periodic inspections of electrical equipment. The inspection includes a visual inspection and an inspection by measuring and testing. This inspection may be carried out by at least one "Sufficiently Trained Person." This person does not have an electrical engineering background but does know how to inspect electrical equipment and similar equipment.


Ad. 3. Instruction of persons
Persons working on and around electrical installations must be periodically instructed on the hazards they may encounter. This safety instruction applies to both electrical and non-electrical personnel. The instruction must address the electrical hazards to which they are exposed during their work. This applies to both electrical and non-electrical work.

Author: Willem Verwoerd, MSc and Richard Winter, MSc

We want to import a medical product from China and have it packaged in Germany. We would prefer not to put the country of origin, China, on the product. What is required to put 'Made in Holland' on it?

 

Answer

Whether you can put 'Made in Holland' on the product depends on where the product was made or where it underwent a last substantial transformation. But what exactly is a 'last substantial transformation'? EU Regulation 2913/92 defines it as follows: 

Goods whose production involves two or more countries shall be deemed to originate in the country where the last substantial transformation or processing, carried out in an undertaking equipped for that purpose, which results in the manufacture of a new product or represents an important stage of manufacture, has taken place.

This leads to a point of discussion as to whether the operations in China fall under this or not. I cannot really give an opinion on that, but the Medical Devices Regulation states the following about the country of origin:

The labelling must include the following information:
a) the name or trade name and address of the manufacturer. In the case of devices imported into the Community for distribution there, if the manufacturer does not have a registered office in the Community, the name and address of the authorised representative must also be stated on the label, on the outer packaging or in the instructions for use;

So, if the product undergoes the last real operation/processing in China, this would mean that you also have to mention that country on the packaging.

However, this is a difficult discussion about what the final manufacturing step is. Honestly, it doesn't seem like the Netherlands anyway.

 

Author: Dr. Rick Elbersen

If you are an importer, and therefore purchase products from outside the EEA (European Economic Area), you are expected to assess whether the goods comply with the relevant Directives. In practice, we often see long lists of products, and this seems unfeasible, but in reality, it's not too bad.

How do you approach this? The best way is to add a few columns behind the product list and mark under which Directive or Directives each product falls. This is often already in an XLS. Depending on the importer we are working with, we then add a number of directives (in those extra columns, such as the Machinery Directive, the Low Voltage Directive, the EMC Directive, the RED, the PED, and often also the RoHS).

 

This gives you insight at a glance into what documentation should be available for the products. Our experience shows that it is best to request the following documentation from the foreign company:

1. Certificates of Compliance for CE-marking
2. Test Reports for CE compliance
3. RoHS compliant report (if it contains electricity or electronics)

And then see what they provide. If your supplier has emailed such documents, you need to check your list to see if this is sufficient proof that the product meets the requirements (at least on paper). If your XLS list states that the Machinery Directive, the Low Voltage Directive, EMC, and RoHS apply, then you should be able to see that in their documentation. And if the supplier doesn't respond, we often know enough.

Documents from manufacturers outside the EEA are often prepared by a test house or Notified Body, and note that you often receive one A4 document (Certificate of Compliance) stating that product X complies with Directive Y, but a test report should also accompany this; also request that, because the last pages of that test report contain photos of the product and the test setup. Check whether the documents are complete and verify against your XLS whether all boxes can be checked off.

As an importer, you also have some additional obligations, such as:

We always include such requirements in separate columns in that specific product list, and a checkmark can then be placed if product X is compliant.

All in all, not complicated, but often a painstaking task to set it up properly from scratch.

Good luck! Or we'll just drop by for a coffee.

 

Richard Winter and Philip Warneke

 

NEN 3140 covers the designation of persons and the inspection of electrical installations and work equipment. We begin with an explanation of the designations, followed by the inspections further down this page.

The designations

According to NEN 3140, persons must be designated by or on behalf of the person at the highest level of responsibility within the organization for compliance with the Working Conditions Act.

The following persons must be designated in writing:

• The installation manager - IV
• The work supervisor - WV
• The skilled person - VP
• The instructed person - VOP

The above-mentioned persons may belong to your organization's staff, but may also be third-party personnel; with the exception of the Installation Manager, this role is reserved for your own company.

Hired personnel, such as temporary agency workers who do not have an employment contract with the organization, perform their work under the direction of your organization. For these individuals, a written designation from their own company is required.

Before a person is designated as an installation manager, work supervisor, skilled person, or instructed person, it is necessary to verify whether they meet the criteria set out in NEN 3140. If their knowledge is sufficient, the person receives a written designation from the Installation Manager. If not, the person must first acquire the knowledge through instruction and/or training.

Because there are many organizational requirements, we have developed a template for an NEN 3140 policy. We have highlighted parts in yellow where you can fill in, for example, who is designated for which role.

You can find this NEN 3140 policy document here.

We have also developed various courses that conclude with a certificate, such as:

the Course: Installation Manager and Work Supervisor

the Course: Skilled person

and Course: Instructed person

In addition, we have supported many companies in drafting an NEN 3140 policy as well as providing various in-company courses. We tailor these to the company, as every situation is different in the electrotechnical field.

The inspections

The inspection of electrical appliances consists of a visual check and several measurements that must be carried out with a suitable measuring instrument. You will find the frequency and whether this is annual or otherwise in a separate appendix in NEN 3140. In practice, with few exceptions, the frequency is almost always once per year.

Further explanation can be found here:

What does the visual check consist of?

The visual check includes, among other things, the mechanical condition, the state of protective and earth conductors, connection cables, operating controls, and whether the device shows no signs of overheating.

Read more →

Which measurements should you carry out?

The measurements depend on the class of the device. For Class I, you measure the protective conductor and the insulation resistance. For Class II (double insulated), you measure the insulation resistance or the leakage current.

Read more →

How do you measure the protective conductor?

The maximum resistance value depends on the length and diameter of the cord. Place one test probe on the metal frame and the other on the earthing contact of the plug and read the resistance.

Read more →

How do you measure the insulation resistance?

Use a megohmmeter in the "Riso" setting. The insulation resistance of Class I must be at least 1 MΩ, and for Class II at least 2 MΩ. Always measure with the device switch in the "ON" position.

Read more →

How do you measure the leakage current?

A milli-Ampere meter is inserted into the protective conductor. The leakage current may not exceed 1 mA (Class I) or 0.5 mA (Class II). Higher values may apply to certain devices.

Read more →

How do you measure the leakage current for PCs, etc.?

For data processing equipment such as PCs, perform a visual check and measure the protective conductor and the leakage current. Due to built-in interference suppression filters, the measurement method differs slightly.

Read more →

Who is authorized to perform these inspections?

The so-called Instructed Person (VOP) is allowed to test electrical appliances. This person does not need to have an electrotechnical education, but must be instructed on electrical hazards.

Read more →

Are you allowed to inspect your own equipment?

Yes. According to Working Conditions Decree art. 7.4-a, anyone with sufficient knowledge and resources may perform the periodic inspection. There is no legal obligation to engage an independent third party.

Read more →

Can you measure equipment made entirely of plastic?

For fully insulated equipment, you cannot measure the protective conductor. Check the type plate for the double-insulation symbol (two squares) and set your measuring instrument to Class II.

Read more →

How do you inspect a site distribution board? (FAQ)

Perform a visual inspection and measure the protective conductor up to the protective contacts. Check whether the residual current device (RCD) is type A with a tripping current of a maximum of 30 mA.

Read more →

What are the differences in requirements between the Netherlands and Germany?

In Germany, inspection is mandatory according to DIN VDE 0701/0702. The inspection points differ slightly from NEN 3140 regarding certain measured values, but the principle is similar. These inspections are mandatory in all EU countries.

Read more →

How do you check a residual current device?

For the protection of persons, 30 mA type A residual current devices must be used. NEN 3140 prescribes periodic checks, including measuring the trip time and testing with the test button.

Read more →

How do you inspect cable reels and extension cords?

The inspection consists of a visual check (cord, plug, housing) and measuring the protective conductor. The maximum allowed resistance value depends on the length and diameter of the cable.

Read more →

How do you inspect a site distribution board?

The periodic check of site distribution boards includes a visual inspection, measuring the protective conductor and insulation resistance, and checking the type of residual current device (type A, 30 mA).

Read more →

How do you make an adapter plug for testing 3-phase devices?

3-phase devices also fall under the periodic NEN 3140 inspection. For this, you need an adapter plug. The inspection points are the same as for grounded Class I devices.

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Tips for purchasing measuring instruments

For NEN 3140 inspection, you need a suitable measuring instrument that can measure the protective conductor, insulation resistance, and leakage current. Read our tips for the right choice.

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After an NEN 3140 inspection, the device no longer works; why is that?

A common problem, especially with fully insulated devices or devices with specific measured values. Read the full explanation for the correct approach and causes.

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Is an NEN 3140 training course mandatory?

No, a training course is not legally required. However, the government requires that you demonstrably possess the knowledge and resources to perform inspections properly.

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Is calibration according to NEN 3140 mandatory?

No, calibration of measuring instruments is not legally required. Companies often include it in their quality system, thereby imposing that obligation on themselves.

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We have also developed a practical online course in which we explain this inspection in a practical way. The course also includes course material and an inspection checklist in WORD. The course concludes with a certificate.

You can find the e-learning Inspection of Electrical Appliances in our shop.

Author: Drs. Richard Winter