Wiha SB25561 Mode D'emploi page 18

Error messages during the installation and function test
The unit may only be used in properly earthed electrical installations!
If an adapter must be used to test a socket or a connecting cable, make sure
that the adapter is in perfect condition and is electrically connected throughout.
The use of adapters without a continuous protective conductor connection will
lead to faulty test results.
Before use, check that the unit is in working order, for example on a known
voltage source.
The tester does not detect reversed N<->PE connections.
Socket inspection
To test sockets and connecting cables, insert the device into the socket. A statement
about the test result is made by means of the display legend below.
L is marked with a red dot on the power plug.
EN
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