Fluke 1550C Manual Del Usurario página 31

Shield
Figure 7 shows how to prevent surface current leakage with a lead connected
from the Guard terminal to a conductor that surrounds the inner insulation. The
surface leakage current is directed to the Guard terminal. This removes the
leakage current from the measurement path between the positive and negative
terminals, and improves the accuracy of the test readings.
Shield
Figure 8 shows how make the measurement setup better. Connect the Guard
terminal to the unused wire and attach it to the inner insulation. This ensures
that the Tester measures the leakage between the selected conductor and the
outer shield, but removes the leakage path between conductors.
Figure 6. Surface Leakage Current
Leakage
Current
Figure 7. Guard Terminal Connection
Insulation Tester
Surface Leakage
Current
Optional
The Tester
( )
( )
GHH13.EPS
( )
( )
G
( )
GHH14.EPS
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