BS/EN 50678-2020 pdf download.General procedure for verifying the effectiveness of the protective measures of electrical equipment after repair.
Tests after repair shall only be performed by an electrically skilled person.
Additional requirements (e.g. for the mechanical safety or for fire protection) according to the requirements from the product safety standard shall be considered.
If testing the equipment requires additional knowledge or additional test and test equipment, for example equipment for microwaves, tests shall be done according to the instructions of the manufacturer.
All tests shall be performed in such a manner that the risk for testing personnel or other individuals shall be reduced by appropriate protective measures.
If not otherwise stated, all values for current and voltage are the RMS values of an alternating, direct or composite voltage or current.
The applicable tests as listed in Clause 5 shall be used to advise that:
— there are no visible faults on safety related parts, which are accessible by the user, arid
— by the intended use of the equipment, no hazard for the user or the environment originates.
The electrically skilled person who is responsible for the test shall decide if additional tests are required to meet the protective measures.
The electrically skilled person may decide that, for equipment that is connected to the distribution system with fixed and protected wiring and is not intended to be hand-held during operation, the test is carried out according to this standard and/or according to HD 60364-6.
The test procedure shall be interrupted, and the equipment shall be disconnected from mains and marked as failed, if it is found that during the test:
— reduced safety levels are present due to damage or from unintended use, and/or
— functional hazards could occur.
5 Tests
5.1 General
5.1.1 General test conditions
The tests may be performed at the ambient temperature, humidity and atmospheric pressure present at the location of testing. The operational limits of the test equipment and the equipment under test (EUT) shall be considered.
The test equipment shall be tested according to the test steps in 5.1.2 to 5.1.5, as long as it is possible with the EUT. The sequence of testing shall be as defined in this standard.
For schematics of test sequences, see Annex B.
Each individual test shall be passed before proceeding to the next test.
If it is not possible to perform a certain test step, an electrically skilled person shall decide if the safety of the EUT can be confirmed without the test step or by other means.
NOTE 1 Manufacturer’s instructions on tests to be performed after repair can be considered as other means.
The values in this standard shall be used unless the product standard specifically provides in-service limits In which case the product standard limits shall be used.
NOTE 2 If other external equipment is connected to the EUT. for example via data connectors, measured values will be for the total system induding the external equipment or accessories, If the external equipment Is disconnected from the mains but remains connected to the EUT, measurements can still be influenced such that it is not possible to correctly access the safety of the EUT.
If it is obvious that the EUT is contaminated by dust or moisture, it is allowed to clean the EUT and/or the EUT is allowed to dry before starting the tests.
5.1.2 Visual inspection
Visual inspection shall be performed according to 5.2.
5.1.3 Test of the protective measures against electric hazards
Test of the protective measures against electric hazards shall be performed according to 5.3 to 5.8.
— Confirmation of the effectiveness of the protective bonding to all accessible conductive parts connected for safety reasons to protective earth according to 5.3.
— Confirmation of the effectiveness of the insulation by measuring the insulation resistance between live parts and accessible conductive parts:BS/EN 50678-2020 pdf download.