KS 3-2010
Page 13
6.3.4 Test
6.3.4.1 All exposed metal parts except line, load, and accessory terminals should be electrically
connected together.
6.3.4.2 Using an insulation resistance tester, apply a voltage of at least 500 volts to determine the
resistance. Voltage is to be applied as follows.
WARNING—High Voltage—Do not touch switch or leads. See 2.1.2 for proper safety procedure.
6.3.4.2.1 Between line and load terminals of each individual pole with the switch in the OFF position
and tripped position if possible.
6.3.4.2.2 Between terminals of adjacent poles with the switch in the ON position.
6.3.4.2.3 From line terminals to the metal enclosure with the switch in the ON position.
6.3.5 Results
All resistance readings should be one megohm or greater for each measurement. If any reading is less
than one megohm, the switch should be replaced or the manufacturer should be consulted before
restoring the switch to service. Any reading less than one megohm may indicate contaminated, unsound,
or cracked insulating material.
6.3.6 Reinstall Switch
If applicable, reinstall the switch following the manufacturer's instructions. Also refer to 5.4 for information
on reinstalling wire connectors and/or conductors.
6.3.7 Reinstallation Procedure
For reinstallation or replacement of the switch and/or accessories, follow the safety installation
procedures given in 2.3.
6.4 Individual Pole Resistance Test (Millivolt Drop)
See
Figure 4, Figure 5, and Figure 6 for typical test set up.
NOTE—The switch should be removed from the equipment for this test. In cases where the switch can be safely isolated as
installed, the test may be performed with the switch in its equipment.
© Copyright 2010 by the National Electrical Manufacturers Association.
To Next Page
Loading...
