Open Circuit Signal Vs Grounded Circuit Signal - Power Probe ECT3000 User Manual

Open Circuit Signal vs Grounded Circuit Signal

Open circuit signals can only be present in a circuit
when there is a resistance of about 100 ohms or great-
er. (Figure A)
If a switch was to close in this circuit, (Figure B) the
open circuit signals would cease to emit and the short/
Grounded Circuit signal would replace it. The trans-
mitter will also sound a tone that tells you that the
circuit has just made contact with ground. (Tip: Wig-
gling and pulling wires that have an open circuit signal
on them can lead you to the problem. This is done by
the transmitter alerting you if the circuit you are pull-
ing on makes contact to a grounded circuit.)
(See: "Circuit Wiggle & Flex Test" pg. 26)
The point here is that Short/Grounded Circuit signals
take priority over open circuit signals. So be sure your
open circuit that you are tracing does not have any
kind of continuity to ground present.
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