Power Probe PPCT - Continuity Tester - Manual (Page 6)

6
Relay Testing
The benefi t of having two tones is
that you can determine the relay coil
from the relay contacts by listening
for the high pitched tone when con-
tinuity is through the coil and the
low pitched tone when continuity is
across good closed contacts. (The
relay coil must have over 10 ohms
resistance for the high pitched tone
to sound). Typical 12V automotive
relay coil resistance ranges from 50
to a few hundred Ohms.
Low
Tone No
Tone
High
Tone
<10
>1k >10
Voltage Detection
(fi g.1) Connecting the SCT’s green lead to ground and then probing the tip into the positive
side of a component that is not yet activated, will sound off a steady high or low pitched tone.
(fi g.2) When the circuit is activated, a warble tone will sound off and alert you to the presence
of voltage on the circuit.
(fi g.1) (fi g.2)
12v
12v
Steady Tone Warble Tone