Snap-On EETA308D, Reference Manual

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3.0 OPERATING INSTRUCTIONS
Refer to Figure. 1 on page 2
3.1 Connecting the probe
To connect the probe to the test equipment, connect
the red plug of the probe connector to CH1 and the
black to GND/COM.
3.2 Switch on
When the probe is turned on, the RED LED
illuminates. You will also notice that when the battery
voltage is too low for normal operation, the LED flashes,
to warn the user that the battery needs to be changed.
The Battery Replacement procedure is described in
section 5.0.
3.3 Low Amp Current Probe Zero Adjustment
The Snap-on Low Amp Current Probe has a push
button auto zero feature. The output zero offset voltage of
the probe may change due to thermal shifts and other
environmental conditions.
To adjust the output voltage to zero:
1. Ensure that the probe is away from the current
carrying conductor.
2. Connect the Low Amp Current Probe to your
instrument and select the voltage scale to view the
reading.
3. Turn the Low Amp Current Probe on by using
the On/Off and Range Selector switch to select the
20A or 60A scale. Press the Zero button.
3.4 Error Factor
Current probes work by reading the magnetic field around
a conductor. The error factor is the amount of induced
error or false reading from a current probe. Some current
probes can have an error factor of over 100 mA. This
induced error reading can be caused by many magnetic
fields. Any device that generates a magnetic field can
induce an error. Even the earth’s magnetic field has an
influence on current probes. To reduce the error factor,
zero the Low Amp Current Probe in the same direction
and inclination as intended use!