3.5.1 Difference Meter example of operation
This explanation of the Difference Meter is written in reference to resistance mode
but the explanation applies equally to inductive mode.
Resistance measurement is selected. The Difference Meter is
inactive. Continuity is indicated for C and P leads
First measurement is complete. The Difference Meter is now
active. The first measurement is shown as a green ring at the
centre of the scale with +0% below.
A second measurement is made, the Difference Meter shows
result relative to reference measurement (+30% in this case)
showing an increase. Shown as a blue ring
Note:
For each successful measurement the needle leaves
a blue marker on the Difference Meter (a red marker if the
reading contains noise).
Third measurement is made, the Difference Meter shows it’s
result relative to the first (>+1000% in this case) showing an
increase.
The 1000% difference shows clearly that something isn’t
right. Check the leads, connections, unit under test, etc.
Note:
The units on the main display have changed from µΩ to
mΩ and are now indicated in blue to highlight the change.
Instrument Controls
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DLRO2
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