Master Sales Consultants of Test and Measurement Instruments and Industrial Supplies

Low Resistance OhmMeters


Digital Low Resistance Ohmmeters

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Accurate results in under three seconds
• Auto current reversal cancels standing emfs
• Fuse protected to 600 V
• NiMH battery reduces weight
• 250 mW power limit (with optional override) to avoid heating the test sample
• Automatically detects continuity in potential and current connections
• Visible warning of high voltages present at the terminals
• Visible warning of current flowing in the test sample
• Multiple operating modes including fully automatic
• Alpha-numeric keypad for entering test notes (DLRO10X)
• User setable high and low limits (DLRO 10X)
• Autoranging with Manual option (DLRO 10X)
• Printer output and memory (DLRO 10X)



The MEGGER DUCTER DLRO10 and DUCTER DLRO10X bring new standards to low resistance measurement. Both are fully automatic instruments, selecting the most suitable test current, up to 10 A dc 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 manual selection of the test current. DLRO10X 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 which 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.



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High test current
• Four terminal measurement
• Two measuring ranges (2000 mΩ. and 20,00 mΩ.)and maximum resolution of 0,01 mΩ.
• Protected against inadvertent connection to the mains supply

The BT51 Low Resistance Ohmmeter makes measurements by passing a current through the conductor under test and also monitoring the voltage across it. The test current is limited by a simple current limiting circuit and is measured by monitoring the voltage across a resistor. The test current is maintained at a nominal 2 A, and as the measurement is ratiometric, the reading is unaffected by any current variations.


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High or low output power selection for condition diagnosis
• Rechargeable battery or line power supply, continuous operation, even with dead battery
• 10 A for 60 seconds, less time waiting to cool, great for charging inductance
• High input protection to 600 V, inadvertent connection to line or UPS voltage will not blow a fuse
• Heavy duty case: IP 65 lid closed, IP54 operational (battery operation only)
• Rotary switch selects one of five test modes, including auto start on connection, giving ease of use

Equally at home in the laboratory, the workshop or in the field, on the bench or on the ground, Megger’s new heavy duty DLRO10HD low resistance ohmmeter combines rugged construction with accuracy and ease of use. It features an internal rechargeable battery and can also operate from a mains supply, even if the battery is completely flat.


Digital Low Resistance Ohmmeter

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• Resolution to 0.1 µΩ on 599.9 µΩ range
• Standard accuracy of ±0.25%
• Digital readout

Megger 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.


Digital Low Resistance Ohmmeter

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• Small and weighs less than 32 lbs (15kg)
• Test currents from 10 A to 200 A d.c.
• Filtered direct current output eliminates magnetic transients
• 0.1 µΩ best resolution
• On board memory for up to 300 test results and notes
• RS232 port to download stored results or for real time output to a printer
• Supplied complete with 16 ft. (5m) test leads and download software

The Megger DLRO200-115 measures contact resistance in high voltage circuit breakers, disconnecting switches (isolators), busbar joints, or for any other low resistance measurement.

This test set accurately measures resistances ranging from 0.1µΩ to 1Ω, at high currents.

A versatile instrument, it can provide test currents from 10 amps up to 200 amps, subject to the load resistance and supply voltage. For those applications that demand a smooth dc current, the DLRO200-115 has extra filtering on the output to reduce mains frequency ripple and can drive 200 amps through a total current loop resistance of 11 milliohms. The filtered output of the DLRO200-115 also eliminates magnetic transients that could inductively trip a breaker’s control (bus differential relay), if left in the test circuit.

The unique design allows the weight and size of the DLRO200-115 to be kept to a minimum; the instrument weighs less than 32 lbs. (15 kg). This small size plus a water/dust ingress rating of IP54 makes the test set equally at home in the workshop, on the production floor or in the field.