Megger PAT4DV/3, Руководство пользователя

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Description of Tests
Earth Leakage (Touch Current) Test
Note: the Earth Leakage (Touch Current) test is carried out concurrently with the Operation test.
The earth leakage test determines whether any current is flowing to earth. Normally appliances should have no or very little earth leakage current. The
PAT4 can also detect earth leakage in Class 2 (Double insulated) assets. This enables account to be taken of all leakage paths to earth rather than
just that flowing in the earth wire if applicable. e.g. a Class 2 (Double insulated appliance) could exhibit earth leakage through its mountings or by
operator contact.
To carry out a Touch Current test on a Class 2 asset, the operator should connect the bond test lead to any accessible surfaces of the asset. To carry
out a Touch Current test on a Class 1 asset, connect the bond test lead to any unbonded metalwork on the asset.
During the test the actual mains voltage is also measured at the appliance socket. In order to ensure that the equipment is safe even when the mains
supply rises to its maximum permitted value (253V or 121V in the UK) the
PAT4 calculates and displays the leakage (Touch) current that would flow
at this value.
Fuse Test
During appliance testing it is often necessary to check the integrity of a fuse. PAT4 incorporates an integral fuse tester on the front panel. To test a
fuse hold the fuse to be tested onto the two pads, the PAT4 will bleep if the fuse is intact.
Extension Lead Testing
Most types of extension leads (including IEC leads, 13 Amp extension leads and 110V BS4343 extension leads) can be tested. Leads are tested for
open and short circuits, correct polarity, Insulation resistance, and Earth conductor resistance. A simple visual inspection option is also included. Leads
are tested by connecting between the appropriate 230 V or 110V socket and the IEC Lead test socket on the front panel. Where the lead to be tested
is not compatible with the IEC lead test socket a short adapter lead should be used to make the connection. See ‘Accessories’.