Promax PD-185, Инструкция по эксплуатации

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USER’S MANUAL PD-185
11/2015 Page 19
4.7 Resistance measurements
CAUTION
Turn off power on the test circuit and discharge all
capacitors before attempting in-circuit resistance
measurements. If an external voltage is present across a
component, it will be impossible to take an accurate
measurement of the resistance of that component.
1. Insert the BLACK and RED test leads into the COM and V
Ω
input terminals respectively.
2. Set the rotary selector switch to the (
Ω
) position.
3. Connect the BLACK and RED test probe tips to the circuit or
device under test, making sure it is de-energized first.
4. The resistance in the test leads can diminish accuracy on
the lowest (400
Ω
) range. The error is usually 0.1 to 0.2
Ω
for a standard pair of test leads. To determine the error,
short the test leads together and then use the (
REL )
Relative mode to automatically subtract the lead resistance
from resistance measurements.
4.8 Continuity testing
1. Select the (
Ω /
/ ) position by turning the rotary
selector switch.
2. Press SHIFT until the symbol appears on the screen.
3. Follow steps 1 and 3 as for resistance measurements. An
audible tone will sound for resistance less than
approximately 40
Ω
.