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DLRO10 and DLRO10X
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5. TEST MODES
DLRO10 has 4 test modes which are selected by repeated presses of the Mode button.
At the end of each test, DLRO10 will display the average of the values obtained with
forward and reverse current.
DLRO10X has 5 modes. On DLRO10X these modes are selected from the TEST menu
using the cursor control and Enter key. At the end of a test, DLRO10X will show three
resistance values; that obtained with forward current, that obtained with reverse
current and the average value.
5.1 Normal mode
Normal mode makes a single measurement of the resistance of the sample using
forward and reverse current
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. To make another
measurement, ensure the test leads are connected and press the test button.
5.2 Automatic mode
If Automatic mode is selected, your instrument will remain in a state of readiness
waiting for both the current and voltage measuring leads to be connected to the
test piece. When this is done, a forward and reverse current test will be started
automatically.
To make another measurement simply break contact with the test sample and remake
contact.
For example, if measuring joints in a long bus bar, you may leave the current circuit
connected at opposite ends of the bus bar. Simply making contact with voltage
probes across the joint(s) you wish to measure will then activate the measurement.
5.3 Continuous mode
Continuous mode requires the connections to be made before pressing the Test
button. Your instrument will then repeat its forward and reverse measurements and
display the results approximately every 3 seconds until contact is broken or the Test
button is pressed.
5.4 Inductive mode
DLRO10 and DLRO10X are able to make d.c. resistive measurements on loads that
exhibit an inductive component using the test mode indicated by the inductor symbol
on the DLRO10, or by using the inductive mode on the DLRO10X.
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.
Having selected inductive mode, connect all four leads to the item being tested and
press the Test button.
DLRO will check that all four leads are in adequate contact with the test piece and
will then apply a test current and try to find the correct range. The display will show
1 - - followed by 1 - - - -. During this time you may see the current range increasing
or decreasing.
On the DLRO10 the “I” lamp will flash and the message “Current Flowing” will
appear.
On the DLRO10X display “Precharge” will appear briefly followed by arrows moving
left to right, the test current will auto-range up and then “Measuring” will be
displayed on the screen. Once readings have stabilised, the operator can then press
the test button to stop the test. The instrument will then auto-range down and show
“Discharging” as the energy stored in the inductive load is discharged and finally
“Complete” will be displayed, at this point it should be safe to disconnect the “C”
Leads.
The time required for a stable reading may vary from a few seconds up to several
minutes depending on the inductance and resistance of the test sample. There is no
time limit for the inductive mode test, which will continue until the operator presses
the Test button.
When the test is terminated, the “I” lamp will remain illuminated on the DLRO10
When these messages are extinguished it should be safe to disconnect the “C” leads.
However, the discharge indicator is an active electronic device and should not be
relied upon. You should observe your organisation’s operating procedures.
