E-Check & test reports – Testing electrical systems in accordance with standards
The E-Check is the standard-compliant inspection of electrical systems in accordance with DIN VDE 0100-600 (initial inspection) and DIN VDE 0105-100 (periodic inspection). It documents the safe condition of the electrical installation and is mandatory for landlords, businesses, and after new installations.
Quick info E-Check
- Initial testing in accordance with DIN VDE 0100-600 is mandatory for every new installation.
- Recurring inspection every 4 years (residential buildings) or 1 year (commercial buildings)
- Test report serves as proof for insurance and liability protection
What is an E-Check?
The E-Check is a comprehensive inspection of the entire electrical installation by a qualified electrician. It includes visual inspection, measurements, and functional tests.
Initial inspection (DIN VDE 0100-600)
Mandatory after every new installation or significant change. Checks whether the system complies with current standards and can be operated safely.
Recurring inspection (DIN VDE 0105-100)
Regular inspection of existing systems. Interval: every 4 years for residential buildings, annually for commercial buildings, every 6 months for construction sites.
Important measurements during the E-Check
insulation resistance
Check the insulation of all cables against ground and between each other. At least 1 MΩ at 500 V test voltage. Low values indicate damaged insulation or moisture.
loop impedance
Measures the resistance of the fault loop (phase-PE). Determines whether the fuse trips quickly enough in the event of a fault. The lower the better – limit values depend on the fuse type.
RCD trip time and current
FI circuit breakers must trip within 200 ms (at rated fault current) or 40 ms (at 5× rated fault current). Measurements are taken using an RCD tester—the test button alone is not sufficient.
grounding resistance
Measures the transition resistance of the grounding system. Important for the function of the protective conductor system. Typical value: less than 2 Ω for new systems.
Common deficiencies in the E-Check
These deficiencies are most frequently criticized in e-checks:
Missing residual current circuit breakers
In older buildings in particular, RCDs are either completely absent or only installed in bathrooms. All socket circuits should be protected by a 30 mA RCD.
Inadequate insulation
Brittle cables, damaged sheathing, or moisture in junction boxes lead to low insulation resistance and an increased risk of fire.
Overloaded circuits
Too many consumers on one circuit, undersized cables, or unsuitable fuses. Often found in installations that have been expanded at a later date.
Missing labeling
Circuit breakers without labeling, unknown circuit assignment. This makes troubleshooting difficult and can be life-threatening in an emergency.
Obligations for landlords and business owners
Landlords have a duty to ensure public safety: electrical installations must be in a safe condition. Regular electrical inspections (recommended every 4 years) document this. Businesses must comply with DGUV Regulation 3: electrical systems and equipment must be inspected regularly. The inspection intervals depend on the type and use of the system.
Practical tips for e-checks and test reports
1. Always fill out test reports completely
In the event of damage (fire, electrical accident), the test report is the most important piece of evidence. Incomplete reports can be used against you in the event of liability.
2. RCD test: Measure tripping time AND tripping current
The test button on the RCD only tests the mechanics. Only a measurement with the RCD tester confirms that the RCD trips within the standard limits.
3. Insulation measurement with disconnected devices
Electronic devices (LED drivers, inverters, UPS) can distort the insulation measurement. Disconnect sensitive devices before taking the measurement.
4. Add photo documentation
Add photos of the meter cabinet, the distribution system, and any conspicuous areas to the inspection report. This saves time during follow-up inspections and serves as a reference.
Conclusion: E-Check protects people and safeguards liability
Regular electrical inspections are not only a legal requirement, but also protect against electrical accidents, fires, and liability risks. The inspection report is your most important document.
Important: E-checks may only be carried out by registered electrical contractors. Make sure they are qualified and ask them to provide you with a complete test report.