Amprobe AM-140-A User Manual
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Note: Normal forward voltage drop (forward biased) for a good silicon diode
is between 0.400V to 0.900V. A reading higher than that indicates a leaky
diode (defective). A zero reading indicates a shorted diode (defective). An OL
indicates an open diode (defective). Reverse the test leads connections (reverse
biased) across the diode. The digital display shows OL if the diode is good. Any
other readings indicate the diode is resistive or shorted (defective).
µA, mA, A, and %4-20mA Current functions
Insert the red test lead into the correct µA/mA or A input jack. Press SELECT
button momentarily to select DC, AC, or DC+AC. The new settings will be
saved automatically to the non-volatile memory as power up default. In DC
mA function, neither in AC nor in DC+AC, press and hold the %4-20mA (
Hz) button for 1 second or more to display the current digital data in terms of
loop current percentage (%) value. It is set at 4mA = 0% (zero) and 20mA =
100% (span) with 0.01% high resolution, which virtually extends the meters’
capability to test and regulate the externally powered loop current in the
industrial process control applications. The analog bar-graph remains showing
the mA current value to alert the user.