Hand held instruments like multi-meters and Insulation Testers are now a given but with the improvement of battery technology and smaller lower power components, many larger instruments are shrinking to hand-held sizes and weights.

Swedish manufacturer DV-Power is the industry leader in pulling the size and weight out of previously large test instruments, the latest being the hand held Transformer Ohmmeter & Ratiometer.

Hand-held Transformer Ohmmeter & Ratiometer

The new DV-Power TWR-H combines two previously mains powered instruments each weighing several kg into a single handheld unit, powered by a Li-Ion battery and tipping the scales at just 1.4kg.

Despite the compact size, performance has not been compromised with winding resistance measured at up to 10 Amps, ratio measured at up to 40V plus the transformer is demagnetised after test! Accuracy is a respectable 0.5% for winding resistance and 0.2% for ratio.

The Lithium-Ion battery has sufficient power for a full day of testing plus it can continue to be used while charging from the mains!

300Amp Micro-ohmmeter

The TWR-H follows on from the success of the RMO-H handheld Micro-ohmmeter.

Using the latest Lithium-Polymer battery technology, the DV-Power RMO-H micro-ohmmeter weighing less than 1kg, can deliver up to 300 Amps test current and perform up to 1000 tests before the battery requires a 2 hour re-charge.

The RMO-H is weatherproof to IP54 and is ideal for testing all types of circuit breaker and switch contacts, high current bus bar joints, cable crimps and splices and welded connections.

Test current is selectable from 1 to 100, 220 or 300A, depending on the model. The current is ramped up to the selected value and ramped down at the end of the test to decrease magnetic transients.

Measurements are at a class leading resolution of 0.1µΩ and accuracy of ±0.1%, each around 10-times superior to other battery powered ohmmeters.

The optional Kelvin spike probes with remote start trigger allow one person to hold a probe in each hand and operate the instrument.

Hand-held Circuit Breaker Analysers

The DV-Power CAT-P began the trend to hand held test equipment and was followed by the CAT-H.

Both models are Li-Ion battery powered giving up to 8 hours of testing, weigh just 1.5kg and feature a 5.7” full colour touch screens, with the ability to overlay up to 4 test records for on-site analysis of test results exceeding the capability of larger mains powered analysers.

The Hand-held CAT’s will perform multiple functions including:

  • Timing of up to 3 main contacts including pre-insertion resistors and auxiliary contacts
  • Resistance of pre-insertion resistors
  • Synchronisation between contacts
  • Main contact bounce time measurement
  • Graphical coil current measurement with AC/DC current clamp
  • Substation battery voltage measurement to 300V
  • Actuation of the breaker open and close
  • First trip test (CAT-P)

With a large 145mm colour touch-screen, the CAT-P can operate independently from a PC or a tablet however DV-Win software is included to allow full PC control and saving of data if required.

The internal memory stores up to 2000 test results, alternatively results can be saved on a USB flash drive

Results screen showing coil current & voltage and timing of main contacts

Traces can be toggled on/off or zoomed for detailed analysis

Up to 4 test results can be overlaid for easy comparison

Hand-held Oscilloscope

While hand held oscilloscopes are not new, few, if any offer both isolated channels and a full colour screen with LED backlighting.

The AEMC OX 5042 has two fully isolated 600V channels with three modes of operation:

  • 40MHz oscilloscope
  • Two 8000 count TRMS multimeters and power analyser
  • Harmonic analyser

The OX-5042 has 2MB of memory allows the storage of 2,700 measurements from 5min to 1 month and communicates with a PC via an isolated optical USB interface.

The included SX-METRO data processing software can be used to:

  • View traces on a PC in real time
  • Control the oscilloscope via the PC
  • Import traces stored in the oscilloscope’s memory or as image files
  • Store traces in text format on the PC
  • Transfer data or waveforms into Microsoft® Excel
  • Use Excel’s functions to perform additional calculations on the data
  • Insert a graph of data from the signal in a report produced using your word processor

The complete range of DV-Power and AEMC instruments are fully supported locally Australian & New Zealand warranties backed by local traceable calibration and service.