247000 Series
Digital Low Resistance Ohmmeters
■
Resolution to 0.1 µΩ on 599.9 µΩ range
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Standard accuracy of ±0.25%
■
Digital readout
247000 Series
Digital Low Resistance Ohmmeters
DESCRIPTION
Digital Low Resistance Ohmmeters (DLRO
®
) are a family of
highly accurate instruments that provide a simple, practical
and reliable means of making low-resistance tests in the
field. They also are ideal for production quality control.
They operate on the four-wire measurement principle, thus
eliminating lead and contact resistances. With basic
accuracies of ±0.25% and resolution down to 0.1 µΩ, they
are nonetheless designed to be rugged and portable for
use at the job site. A variety of optional test leads and
calibration resistance standards are offered for use with
DLROs.
APPLICATIONS
Operation is simple: just connect the leads, turn the
instrument on and read the measurement directly from
the digital LED display. No warm-up is required.
Typical applications include measuring the resistance of:
■
Switch and circuit breaker contacts
■
Transformers and generators
■
Motor windings
■
Busbar and other joints
■
Aircraft, rail and pipe bonds
■
Cable splices, welds and fuses
■
Metal alloys
■
Graphite electrodes and other composites
■
Wire and cable
General-Purpose DLROs
Two models specially designed for general-purpose testing
applications are available.
Each provides up to 10 amperes of test current for
measuring resistances to 60 ohms with 1 µΩ resolution
and ±0.25% accuracy.
Dual-Pak General-Purpose Model, Cat No. 247000
This battery-powered unit features separate measuring and
charger modules for maximum portability. The charger can
be left in the shop, and the measuring module taken to
the job site.
It weighs less than 8 pounds (3.6 kg) and provides hours
of testing.
Single-Pak General-Purpose Model, Cat. No. 247001
This compact instrument packages measuring circuits,
rechargeable batteries and charger in one self-contained
unit.
Ruggedly built to handle the most demanding field
applications, the Single-Pak is housed in a tough Noryl
®
case with hinged, removable lid and carrying handle.
This model also includes captive wing nuts.
Single-Pak/Low-Range Model
Cat. No. 247002
This model provides an extra range, 0 to 599.9 µΩ, for
applications requiring 0.1 µΩ resolution. It also features a
current-reversing switch to average out any voltage offset
in the test sample. Captive wing nuts are also standard.
247000 Series
Digital Low Resistance Ohmmeters
Low-Range/High-Current Models
Cat. No. 247100 and 247101
These instruments are used when a continuous test current
of 100 amperes is required. These models include a
separate 100 ampere current supply module with a
modified standard battery-powered 10 ampere system.
These combinations provide a sixth range, 0 to 599.9 µΩ,
with the 100 ampere current.
For 100 ampere measurements, an interconnecting cable
from the 100 ampere current supply module is plugged
into a special receptacle on the measuring module.
When the 100 ampere range is not used, a jumper plug is
inserted in place of the interconnecting cable.
This feature allows the measuring module to be used
as a standard battery-powered, 10 A instrument.
Cat. No. 247100 meets ANSI C37.09, Test Procedure for
AC High Voltage Circuit Breakers.
FEATURES AND BENEFITS
■
Resolution as fine as 0.1 µΩ
■
Standard accuracy of ±0.25%
■
Kelvin-type, four-wire measurement eliminates errors
caused by lead and contact resistances.
■
Digital readout with automatic zero circuit eliminates
field test inaccuracies.
■
Broad line of test leads is available to simplify and
enhance data collection.
The Low-Range DLRO, Cat.
No. 247002, features an extra
range and rugged, Single-Pak
design.
Low-Range/High-Current Model Cat. No. 247101 consists of a
Single-Pak DLRO, Cat. No. 247001-3, and separate 100 ampere
test current supply, Cat. No. 247120. The 100 ampere supply
also may be ordered as an option.
SPECIFICATIONS
Cat. No. Model Resistance Resolution Current Accuracy Power Dimensions Weight
Range Source
247000 Dual-Pak 0-5.999mΩ 1µΩ 10A Rechargeable 8Hx9Wx8D in. 12.25 lb
0-59.99mΩ 10µΩ 1A batteries with (20 x 23 x 20 cm) (5.6 kg)
0-599.9mΩ 0.1mΩ 100mA (0.25%rdgd separate
0-5.999Ω 1mΩ 10mA + 1 lsd) charger
0-59.99Ω 10mΩ 1mA
247001 Single-Pak 0-5999µΩ 1µΩ 10A Rechargeable 12Hx6Wx10D in. 12 lb
0-59.99mΩ 10µΩ 1A batteries with (30 x 16 x 25 cm) (5.5 kg)
0-599.9mΩ 0.1mΩ 100mA (0.25%rdgd internal
0-5.999Ω 1mΩ 10mA + 1 lsd) charger
0-59.99Ω 10mΩ 1mA
247002 Single-Pak 0-599.9µΩ 0.1µΩ 10A Rechargeable 12Hx6Wx10D in. 12 lb
Low Range 0-5.999mΩ 1µΩ 10A batteries with (30 x 16 x 25 cm) (5.5 kg)
0-59.99mΩ 10µΩ 1A (0.3%rdgd internal
0-599.9mΩ 0.1µΩ 100mA + 1 lsd) charger
0-5.999Ω 1mΩ 10mA
0-59.99Ω 10mΩ 1mA
247100 Low Range 0-599.9mΩ 0.1µΩ 100A (0.5%rdgd Line Operated 13Hx8Wx10D in. 20 lb
Power Pak + 2 lsd) Supply (33x20x25 cm) (9.3 kg)
247120
247101 Higher 0-5.999mΩ*1µΩ 10A (0.25%rdgd Rechargeable Dual -Pak units 12 lb
Ranges 0-59.99mΩ 10µΩ 1A + 1 lsd) batteries with 8Hx9Wx8D in. (5.5 kg)
Measuring 0-599.9mΩ 0.1mΩ 100mA separate (20 x 23 x 20 cm)
Modules 0-5.999Ω 1mΩ 10mA charger or
247000-3 0-59.99Ω 10mΩ 1mA internal Single-Pak
or or charger 12Hx6Wx10D in.
247001-3 0-5999µΩ* (30 x 16 x 25 cm)
247100 consists of 247000-3 Dual-Pak & 247120 100 ampere Power Supply
247101 consists of 247001-3 Single-Pak & 247120 100 ampere Power Supply