Power Probe ECT 2000 - Manual (Page 22)

22
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 greater.
(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 SMART
transmitter 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 SMART transmitter alerting you if the circuit you
are pulling 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.