Amprobe 38SW-A, User Manual

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3
Introduction
The 38XR-A is a true rms autoranging handheld digital multimeter for measuring or
testing the following:
•
DC and AC Voltage
•
Capacitance
•
DC and AC Current
•
Diodes
•
Resistance
•
Continuity
•
Frequency
•
dBm
•
Dutycycle
•
4 - 20 mA Loop Current
•
Temperature
Additional features include: MIN MAX AVG, HOLD, REL, PEAK±, Range Lock,
RS-232 IR communication, and Backlight.
Making Measurements
Verify Instrument Operation
Before attempting to make a measurement, verify that the instrument is operational
and the battery is good. If the instrument is not operational, have it repaired before
attempting to make a measurement.
Range Selection
In addition to autoranging the 38XR-A allows you to manually select and lock a
range by pressing the
RANGE button. RANGE appears on the display to indicate
that manual ranging is active and the range is locked. When appropriate, each
subsequent press of the range button steps the meter to the next higher range.
When the highest range is reached the next press returns the meter to the lowest
range. To return to autoranging press and hold the
RANGE button for 2 seconds. If
RANGE still shows on the display, autoranging is not appropriate for the selected
function.
Use autorange for all initial measurements. Then, when appropriate, use the
RANGE
button to select and lock a range.
Warning
To avoid electrical shock while manual ranging use the display
annunciators to identify the actual range selected.
Correcting an Overload (
o
or
- o
) Indication
W
An
o
or
- o
indication may appear on the display to indicate that an overload
condition exists. For voltage and current measurements, an overload should be
immediately corrected by selecting a higher range. If the highest range setting does
not eliminate the overload, interrupt the measurement until the problem is identified
and eliminated. The
o
indication is normal for some functions; for example,
resistance, continuity, and diode test.