Atec DLRO-10X User Manual

DLRO 10 and DLRO 10X

Digital Microhmmeter

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DLRO 10 AND DLRO10X

Digital Microhmmeter

Auto current reversal cancels standing
emfs

Protected to 600 V

Automatically detects continuity in
potential and current connections

Multiple operating modes including fully
automatic

Alpha-numeric keypad for entering test
notes (DLRO 10X)

DESCRIPTION

DLRO 10 and DLRO 10X set the standards for low resistance
measurement. DLRO 10 and DLRO 10X are fully automatic
instruments, selecting the most suitable test current up to 10 A
d.c. to measure resistance from 0.1 µΩ to 2000 Ω, on one of seven
ranges.

For users who desire more control over the measurement process,
DLRO 10X uses a menu system controlled by a two-axis paddle to
allow the user to manually select the maximum test current.

DLRO 10X also adds real time download of results and on board
storage for later download to a PC.

Both instruments are built into a strong, lightweight case that is
equally at home in the field or in the laboratory. Light enough to
be worn around the neck, they are small enough to be taken into
areas that were previously too small to access.

DLRO 10 uses a large, bright 4 1/2 -digit LED display while DLRO
10X has a large, backlit LCD display. Normally, measurements are
made with forward and reverse currents to cancel the effects of
any standing voltages across the test sample.

The average value is then displayed within 3 seconds, to a basic
accuracy of 0.2%. DLRO 10X displays both forward and reverse
measurements as well as the average of the two.

DLRO 10X allows the user to set high and low pass limits, thereby
enabling simple go-no-go testing.

At the end of a test DLRO10X will store the test results, as well as
any notes relevant to the test.

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User selectable high and low limits
(DLRO 10X)

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Printer output and memory (DLRO 10X)

To assist operator safety and ease of use, both instruments are
supplied complete with a pair of duplex handspikes with 1.2 m
(4 ft) leads. One of the probes is fitted with LED’s, which duplicate
indicators on the instrument display indicating that all four contacts
have been made, the presence of a high voltage across the load,
and the presence of current flow while a load is discharging. A full
range of test leads is available with probes, clamps and Kelvin clips.

Nickel Metal Hydride (NiMH) batteries power the instruments.
The battery packs are interchange-able so that an exhausted battery
may be recharged using the external charger supplied while testing
continues using a spare pack. Although full charging will take 4 hours,
a fast charge mode allows the battery to be 90% charged within
2 1/2 hours from a 12 volt battery or from a standard 120/230 V AC
supply via the supplied charger. The battery pack contains its own
battery state indicator, which allows the charge-state to be monitored,
even without being connected to the instrument.

DLRO 10X is fitted with RS232 communications that will allow
results to be downloaded in real time or stored for later retrieval.

Up to 700 sets of results may be stored within DLRO 10X complete
with notes containing up to 200 characters which may be added
using the on board keypad. These results can also be downloaded
to a PC.

MEASUREMENT MODES:

A variety of measurement modes are available. Since the introduction
of V2.0 firmware, Normal, Auto, Continuous and Inductive mode
are available on both the DLRO 10 and the DLRO 10X.

DLRO 10 AND DLRO 10X

Digital Microhmmeter

DLRO 10 will display the average of the measurements achieved
using forward and reverse current, while DLRO 10X displays both
individual measurements and the average.

Normal mode initiates a test by pressing the Test button on the
instrument front panel after connecting the test leads. Continuity
of all four connections is checked, forward and reverse currents
are applied.

Auto mode allows forward and reverse current measurements to
be made and the average displayed simply by making contact with
all four probes. 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 on the instrument.

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 3 seconds until the
circuit is broken.

Inductive mode is intended for use when measuring inductive
loads. When measuring inductive loads it is necessary to wait for
the voltage to stabilise. This means that the measurement could
take a few seconds or several minutes. The test leads are firmly
connected to the item to be measured and the Test button is
pressed. The instrument will pass a current through the sample
and wait for the voltage to stabilise. If possible the current will
be increased. This procedure will be repeated until the voltage
detected falls into the range 15 mV to 200 mV. The instrument will
then continue to take readings, which will gradually decrease to the
true value as the voltage stabilises further. The operator decides
when the result is stable and presses the test button to terminate
the test. Measurement is made with forward current only.

Unidirectional mode, on DLRO 10X only, applies a current in one
direction only. This does not enable any standing emfs to be negated
but speeds up the measurement process. Test starts automatically
when probes are connected.

FEATURES AND BENEFITS

n Small, lightweight and portable - can be used in tight places,

reduces the need for extra long leads and two person operation.

n Four terminal resistance method shows the true resistance of the

item under test.

n Bright LED (DLRO 10) and LCD (DLRO 10X) displays are easily

visible under all lighting conditions and reduce human error.

n Automatically applies forward and reverse currents which cancel

out any standing voltages across the sample under test.

n Checks for undue noise during measurement, reducing the

possibility of recording the incorrect result.

n Automatically detects continuity in P and C circuits, preventing

erroneously high reading to be taken due to high resistance
contact.

n Battery module has a battery condition indicator allowing the

user to check the state of spare batteries without connecting to
the instrument.

n RS232 connector on the DLRO 10X allows downloading of results

in real time or stored for later retrieval.

APPLICATIONS

The needs for accurate low resistance measurement are well
known and very diverse. They range through Goods Receiving
inspection of components to ground bonding and welded joints.
Typical applications include, but are not limited to, making d.c.
resistance measurements of:

n Switch and contact breaker resistance

n Busbar and cable joints

n Aircraft frame bonds and static control circuits

n Integrity of welded joints

n Inter-cell connections on battery systems up to 600 V peak

n Quality control of resistive components

n Transformer and motor winding resistance

n Rail and pipe bonds

n Metal alloys, welds and fuse resistance

n Graphite electrodes and other composites

n Wire and cable resistance

n Transmitter aerial and lightning conductor bonding