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PAT400 Series
28
3.11
Cable compensation
A power cord, appliance lead or extension lead will frequently exceed the nominal length and consequently the resistance limit set in the
standard test groups.
Rather than having many test groups with different lead lengths, the “Cable Resistance Calculator” screen allows the limit of a Bond or
Continuity test to be modified after the measurement. On a failed test, entering the length of the lead and the conductor cross section,
the pass limit is adjusted to the correct resistance. The result is then passed or failed, as necessary.
To apply cable resistance calculation:
1)
When a continuity or Bond test fails, the screen message alert will be displayed:
2)
Press OK to access the Cable Resistance Calculator as below;
OR
Press Esc to fail the Asset and save or abort the results,
OR
Press “R” to re-run the continuity test.
3)
Enter the cable Length in metres and the conductor Cross-Section (mm2) OR a Resistance can be entered if this is known.
4)
Press TEST to complete the test. The PAT400 will now proceed to the next test if the resistance was a PASS or to a fail screen if
the resistance was still outside the modified limit.
See also Section A.6 for cable length limitations and RCD protection on long leads.
