7
Test modes
Test mode, is selected by a six (including off) positioned rotary selector
switch that activates the following modes:
Normal mode
– The test is initiated by pressing the ‘Test’ button after
connecting the test leads to the unit under test. Continuity of all four
connections is checked. Current is applied in both forward and reverse
direction following which the measurement result is displayed. Please note
that in this mode both the current and voltage leads must be connected
across the test sample before the Test button is pressed.
Automatic mode
– The test is started as soon as the probes make contact.
Forward and reverse current measurements are made and the average value
is displayed. This mode is ideal when working with the supplied handspikes.
Each time the probes are removed and reconnected to the load another test
will be performed without the need to press the test button.
Automatic unidirectional mode
– Here current is applied in one direction
only to speed up the measurement process. However standing EMF’s
setup during the test are ignored so lower accuracy can result. Test starts
automatically when probes are connected. To make another measurement
simply break contact with the test sample and remake contact on next test
sample.
Continuous mode
– Allows repeated measurements to be made on the
same sample. Simply connect the test leads and press the test button. The
measurement is updated every three seconds until the circuit is broken.
Please note that in this mode both the current and voltage leads
must be connected across the test sample before the Test button is
pressed.
Inductive mode
– When measuring inductive loads it is necessary to wait
for the voltage to stabilise, so the measurement process can take a few
seconds or several minutes. The test leads are firmly connected to the item
to be measured and the ‘Test’ button pressed. The instrument will pass the
selected current through the sample continuously in one direction only. The
instrument will take repetitive readings, which will gradually decrease to the
true value as the voltage stabilises. The operator decides when the result is
stable and presses the ‘Test’ button to terminate the test.
When measuring
inductive loads it is essential that the current carrying leads are
securely clamped to the item being tested and that they are not
removed before any stored charge has been discharged at the end
of the test. Failure to comply with these instructions might result in
an arc being produced, which might be dangerous for the instrument
and the operator.
Automatic modes -
bidirectional and
undirectional
current flow
Continuous mode -
test current applied
in both directions,
test repeated at 3
seconds intervals
Normal mode -
test current applied
in both directions
undirectional
current flow
Instrument is off in
this position
Inductive mode –
test current applied
in one direction
only
