After a VDE inspection, it is not only important that an electrical installation has been technically tested. It is equally important that the results are documented in a traceable way. An inspection report must show what was tested, which measuring device was used, which measured values were recorded and how these values were assessed.
In practice, many uncertainties do not arise during the measurement itself, but during documentation. Is a note saying “OK” sufficient? Which measured values belong in the report? Does the calibration status of the test instrument have to be stated? And how should defects, extensions or periodic inspections be documented correctly? This article explains which information should typically be documented in a VDE inspection report and why complete documentation is so important for electrical contractors, facility management, industry, landlords and quality management.
Suitable VDE test instruments, installation testers for VDE 0100 installation testing and modern test instruments with memory and documentation functions are used for carrying out and documenting such inspections.
Table of contents
- Why a VDE inspection report is more than a formality
- Clearly defining the scope of inspection: What was actually tested?
- Correctly documenting information about the installation or test object
- Specifying measuring device, serial number and calibration status
- Documenting the visual inspection: The first important part of the VDE test
- Protective conductor and continuity: Which values are important?
- Insulation measurement: Recording measured values in a traceable way
- RCD testing: Documenting tripping time and tripping current
- Documenting loop impedance and internal network resistance
- Recording voltage, phase sequence and functional tests
- Describing assessment, defects and corrective measures clearly
- Digital documentation: Why memory and software save a lot of time
- Practical example: Extension of an electrical installation
- Suitable test instruments for VDE testing and documentation
- Conclusion: A good inspection report makes the VDE test traceable
- FAQ: Frequently asked questions about VDE inspection reports
Why a VDE inspection report is more than a formality
An inspection report is not just a document for filing. It is written proof that an electrical installation, a circuit, an extension or a piece of equipment has been tested and assessed. Especially with electrical installations, it is not enough to simply state that “everything works”. What matters is whether the protective measures are effective and whether the measured results provide traceable evidence that the installation can be operated safely.
For electrical contractors, the inspection report is an important part of proper handover. For operators, facility management or industrial companies, it serves as evidence for internal responsible persons, insurers, auditors or authorities. Clean documentation is also valuable for later faults, modifications or periodic inspections, because previous measured values can be compared with current results.
A good inspection report therefore answers several questions at the same time: Which installation was tested? Which circuits or items of equipment were part of the inspection? Which test methods were used? Which measured values were recorded? Were limit values complied with? Were there any defects? And when is the next inspection due?
Clearly defining the scope of inspection: What was actually tested?
A common weak point in inspection reports is an unclear scope of inspection. Especially in larger buildings, production facilities or after subsequent extensions, it must be clearly described which areas were tested and which were not. Otherwise, it is later hardly possible to determine whether the report refers to the entire installation, only to a sub-distribution, a single machine, a newly installed circuit or an extension.
For an initial inspection after installation or extension of an electrical system, documentation is particularly important. For example, if a new sub-distribution has been installed, an additional machine connection has been created or a storage area has been electrically extended, the inspection report should clearly show which circuits are affected. A general statement such as “electrical installation tested” is usually too imprecise in such cases.
A clear description of the inspection area is useful, for example by specifying the building, floor, room, distribution board designation, circuit numbers, installation identification or machine designation. The more precise this information is, the easier it is to assign measured results later.
Correctly documenting information about the installation or test object
The basic data of the tested installation or tested part of the installation should be stated at the beginning of an inspection report. This includes the client, location, installation designation, distribution board or circuit, inspection date and responsible qualified electrician. In industrial installations, machine or equipment numbers, cost centers, hall areas or internal system identifiers may also be useful.
At first glance, this information appears organizational, but it is essential for later traceability. If several similar installations, distribution boards or machines are present, a measured value without clear assignment can quickly become worthless. Clear installation structure is therefore particularly important in industry, facility management and periodic inspections.
| Information in the inspection report | Why it is important |
|---|---|
| Location and installation area | Clearly assigns the inspection to a building, room or area |
| Distribution board or circuit designation | Allows individual measured values to be assigned |
| Inspection date | Important for evidence and later periodic inspections |
| Person performing the inspection | Documents technical responsibility |
| Type of inspection | Distinguishes, for example, initial inspection, inspection after extension or periodic inspection |
Especially with digital inspection reports, it is worth maintaining this master data carefully. Modern test instruments and software solutions can assign measured values directly to installations, distribution boards or circuits. This reduces transmission errors and saves time during later inspections.
Specifying measuring device, serial number and calibration status
An inspection report should not only contain the measured values, but should also show which test instrument was used to record these values. This includes device type, manufacturer, serial number and calibration status. The reason is simple: measured results are only reliable if the measuring device used is suitable and has been tested in a traceable way.
In practice, this point is often underestimated. If an inspection report is reviewed years later or compared with new measured results, it is important to know which device was used and whether its calibration was valid at the time of testing. This information is particularly important in quality management, audits or safety-relevant installations.
Even if a measuring device is regularly checked or calibrated internally, the evidence should be clearly assignable in the inspection report or in the associated documentation. If several test instruments are used in the company, the serial number is essential so that not only the device type but the specific measuring instrument can be identified.
Documenting the visual inspection: The first important part of the VDE test
The visual inspection is an essential part of the VDE test. Many safety-relevant defects cannot be detected by measured values alone. Damaged cables, missing covers, incomplete labeling, unsuitable equipment, loose terminals, incorrect protection ratings or insufficient strain relief are usually identified by inspection.
The inspection report should therefore not only state that a visual inspection was carried out. Depending on the installation, it should be traceable which points were inspected and whether any abnormalities were found. Especially in the case of extensions, it is important to document whether the new installation was carried out professionally and whether it fits the existing installation.
An unobtrusive visual inspection can be documented accordingly in the report. If defects are found, they should be described clearly. A formulation such as “defect present” is not very helpful. A specific description is better, for example “missing labeling, circuit UV-2/F12”, “damaged socket in workbench area 3” or “cover in terminal area not fully closed”.
Protective conductor and continuity: Which values are important?
The continuity of the protective conductor is a central requirement for the effectiveness of many protective measures. If the protective conductor is interrupted, has high resistance or is incorrectly connected, a dangerous touch voltage can remain present in the event of a fault. That is why checking the protective conductor connection is one of the important measurements in electrical installations.
The inspection report should document at which point the measurement was carried out and which measured value was determined. Depending on the installation, it may be useful to assign the measured values to individual sockets, equipment, distribution boards or circuits. This makes it possible to trace later which parts of the installation were actually tested.
With long cable runs, large installations or several sub-distributions, different protective conductor values can occur. It is therefore not sufficient to make only a general note that the protective conductor is “OK”. A specific measured value creates transparency and enables comparison during later inspections.
Insulation measurement: Recording measured values in a traceable way
Insulation measurement is used to assess the condition of the insulation between live conductors and the protective conductor or between live conductors. Poor insulation values can indicate damaged cables, moisture, contamination, connected loads, ageing or installation errors.
The measured insulation values should be clearly documented in the inspection report. It is also important to document the conditions under which the measurement was carried out. In practice, it can make a major difference whether loads were connected, whether sensitive electronics were disconnected or whether certain circuits were tested together.
Especially in installations with electronic equipment, frequency inverters, power supplies or control systems, the insulation measurement must be properly prepared. Otherwise, measured results may be distorted or connected devices may be endangered. The documentation should therefore not only contain the measured value, but also make assignment to the circuit or part of the installation possible.
| Measurement | What should be documented | Why it is important |
|---|---|---|
| Protective conductor continuity | Measuring point, circuit, measured value | Proof of protective conductor connection |
| Insulation resistance | Circuit, test voltage, measured value | Assessment of insulation and possible fault locations |
| RCD test | RCD type, rated residual current, tripping time, if applicable tripping current | Proof of function of the residual current protective device |
| Loop impedance | Measuring point, circuit, measured value | Assessment of disconnection conditions |
RCD testing: Documenting tripping time and tripping current
Residual current devices, commonly referred to as RCDs or FI switches, must disconnect reliably in the event of a fault. It is therefore not sufficient to press only the test button. The test button merely shows that the mechanism generally trips. For assessing the protective function, measured values such as tripping time and, depending on the test, tripping current are relevant.
The inspection report should clearly state the tested RCD, its rated residual current, type and measured values. If there are several RCDs in one installation, it must be clear which value belongs to which protective device. This is particularly important in sub-distributions with several residual current devices or in installations with selective RCDs.
Assignment to the protected circuits is also important. If an RCD later trips or an installation is extended, a good inspection report helps to better understand the protective structure. In special applications, for example charging equipment, frequency inverters or medical areas, additional requirements may apply to RCD type and testing.
Documenting loop impedance and internal network resistance
Loop impedance is an important measured value for assessing whether protective devices can disconnect safely and in time in the event of a fault. If the impedance of the fault loop is too high, the fault current may be too low to trip a fuse or circuit breaker within the required time.
In the inspection report, the measured loop impedance value should be clearly assigned to the respective circuit or measuring point. This documentation is particularly important for long cables, extensions, sub-distributions or sockets at the end of a cable run. It shows that testing was not only carried out at the distribution board, but also at relevant end points.
The internal network resistance can also play an important role, for example in assessing the supply, short-circuit conditions or power quality. Depending on the test instrument and application, these values are automatically stored and can later be transferred into a digital report.
Recording voltage, phase sequence and functional tests
In addition to protective conductor, insulation, RCD and loop measurements, voltage measurements, phase sequence testing and functional tests are also part of the documentation, depending on the installation. Especially with three-phase connections, the correct phase sequence is important. An incorrect phase sequence can cause motors to rotate in the wrong direction or machines not to function correctly.
Functional tests should also not only be confirmed verbally, but recorded in a traceable way. These may include, for example, the function of switches, emergency stop devices, interlocks, indicator lamps, protective devices or control functions. Clear documentation is particularly important for safety-relevant functions.
The type of functional test depends strongly on the installation. Different points are relevant for a simple building installation than for an industrial machine, a sub-distribution, a charging device or a technical plant area. What matters is that the inspection report fits the actual application.
Describing assessment, defects and corrective measures clearly
An inspection report should not only collect measured values, but also assess them. For the operator, it is important to know whether the installation may continue to be operated, whether defects are present and which measures are required. Abnormal measured values, failed tests or visible defects should therefore be described clearly.
For defects, understandable wording is important. It should indicate the location, the type of defect and the recommended measure. A simple note such as “rectify defect” is often not sufficient for later processing. A specific description is better, for example which circuit is affected, which measured value was abnormal or which component is damaged.
Even if no defects were found, the assessment should be clear. This makes it traceable that not only measurements were carried out, but that the measurement result was technically assessed. For periodic inspections, the next inspection date or recommended inspection interval can also be documented.
Digital documentation: Why memory and software save a lot of time
With only a few measuring points, a handwritten or manually completed inspection report may still be manageable. In larger buildings, industrial installations or facility management structures, however, manual documentation quickly becomes prone to errors. Measured values must be noted, transferred, assigned and assessed. Number transpositions, incorrect circuit designations or missing information can occur.
Modern installation testers with memory function, automatic test sequences and software connection can significantly reduce this effort. Measured values are stored directly in the device and later transferred into an inspection report. If the installation structure, distribution boards and circuits are created in advance, measured values can be assigned clearly.
Digital documentation also has advantages for periodic inspections. Previous measured values can be compared with current results. This makes it possible to detect changes, for example increasing loop impedances, deteriorating insulation values or abnormal differences between circuits. For operators and quality management, this creates a much better data basis.
Practical example: Extension of an electrical installation
In an industrial company, an existing sub-distribution is extended. Several new socket circuits and a machine connection are installed. After completion of the work, the installation is to be tested and handed over. At first glance, everything works: the sockets have voltage, the machine starts and the fuses remain switched on.
However, a simple note saying “installation OK” would not be sufficient in this case. For traceable documentation, the newly installed circuits must be clearly named and tested. This includes, among other things, the visual inspection of the installation, the protective conductor test, insulation measurement, RCD measured values, loop impedance values and checking correct assignment in the distribution board.
During measurement, for example, it becomes apparent that a socket circuit at the end of a long cable run has a significantly higher loop impedance than the other circuits. The value must be documented and technically assessed. Only then is it traceable whether the disconnection conditions are fulfilled or whether a change is necessary.
This example shows why an inspection report must do more than provide a simple confirmation. It must show which measurements were carried out, which values were determined and why the installation was assessed as safe.
Suitable test instruments for VDE testing and documentation
Suitable installation testers are required for testing electrical installations, as they can carry out the required measurements safely and in a traceable way. Depending on the application, these include measurements of protective conductor continuity, insulation resistance, loop impedance, RCD tripping, voltage, frequency and phase sequence.
In the VDE 0100 installation testing category, you will find suitable test instruments for electrical installations. Multifunction installation testers such as the GSC60 VDE0100 installation tester and 3-phase power/energy analyzer or devices such as the CA 6163 multitester / machine tester are suitable for extensive test tasks.
If the focus is on efficient test data acquisition, automatic test sequences and documentation, test instruments with memory function and software connection are particularly helpful. They reduce manual effort and make it easier to create traceable inspection reports.
Conclusion: A good inspection report makes the VDE test traceable
A VDE inspection report is much more than a form with measured values. It documents which installation was tested, which measurements were carried out, which test instruments were used and how the results were assessed. Only this makes the inspection traceable later.
Particularly important are clear assignment of measured values, information on the test instrument used and calibration status, documentation of the visual inspection, protective conductor values, insulation values, RCD measured values, loop impedance and a clear assessment of possible defects. A simple “OK” is often not sufficient if it must later be traced why an installation was assessed as safe.
Modern VDE test instruments and installation testers with memory and documentation functions are suitable for efficient and secure documentation. They help to record measured values cleanly, avoid transmission errors and create professional inspection reports.
FAQ: Frequently asked questions about VDE inspection reports
What must be included in a VDE inspection report?
A VDE inspection report should include information about the tested installation, inspection date, person performing the test, test instrument used, calibration status, scope of inspection, tests carried out, measured values and assessment of the results.
Is a note saying “OK” sufficient in the inspection report?
A simple note saying “OK” is usually not sufficient if the inspection is to be traceable later. Specific measured values, clear assignments and a technical assessment of the results are decisive.
Which measured values belong in an inspection report according to VDE?
Typical measured values include protective conductor continuity, insulation resistance, RCD tripping time, if applicable RCD tripping current, loop impedance, internal network resistance, voltage, frequency and phase sequence. Which values are required depends on the installation and the type of inspection.
Does the calibration status of the test instrument have to be documented?
Yes, the calibration status should be documented or clearly traceable. Measured results are only reliable if the test instrument used was suitable and properly checked or calibrated at the time of testing.
Who is allowed to carry out a VDE inspection?
Work and inspections on electrical installations may only be carried out by qualified electricians or under their responsibility. The requirements depend on the installation, activity and company organization.
Why is the visual inspection important in the inspection report?
Many defects cannot be detected by measured values. Damaged cables, missing covers, incorrect labeling or unsuitable equipment are often identified during visual inspection. This test step should therefore also be documented.
How are defects documented in the inspection report?
Defects should be described specifically. Useful information includes the location, the affected circuit or equipment, the type of defect and the recommended measure. General formulations are often not sufficient for later processing.
What are the advantages of digital inspection report documentation?
Digital inspection report documentation reduces transmission errors, saves time and makes it easier to assign measured values to installations, distribution boards and circuits. In addition, previous measured values can be compared more easily during periodic inspections.
Which test instruments are suitable for VDE inspection reports?
VDE test instruments and installation testers are suitable if they can perform the required measurements and ideally store measured values or transfer them to documentation software.
Why is the assignment of measured values so important?
A measured value is only meaningful if it is clear where it was measured. Measured values should therefore be clearly assigned to circuits, distribution boards, sockets, machine connections or installation areas.