Resistance Measurements - Promax PD-181 Manual De Instrucciones

CAUTION
A common abuse of multimeters in to attempt to measure a
voltage while the test leads are still plugged into the current input
terminals. This basically puts a short circuit across the voltage
source since current ranges have a low impedance. If the voltage
source is typically 240VAC or a 3-phase industrial voltage (415V),
very high fault currents can result. This is why all current input
terminal are fused. If the fuses blow they must only be replaced by
the equivalent ones otherwise the safety of the instrument may be
impaired.
7. Never apply a voltage between the COM terminal and current
terminals.
8. When switching between current ranges to obtain greater
accuracy and better resolution, completely de-energize the circuit
to be measured before changing the range.

4.5 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 VΩ
input terminals respectively.
2. Set the rotary selector switch to the (Ω) position. If the indication
of overflow appears, select a top scale.
3. Connect the BLACK and RED test probe tips to the circuit or
device under test, making sure it is de-energized first.
10/06 - 11 - PD-181