OTD Oil Tan Delta



  • Fully automated standard and user defined tests – Supports all international standards
  • Integrated test cell heating and cooling systems
  • Efficient oil fill and integrated automated oil drain facility
  • IEC 60247 Innovative Test Cell – easy to assemble and clean
  • Stores up to 50 records on-board and download to PC
  • Compact and lightweight (22 kg / 48.5 lbs.)

The Oil Tan Delta (OTD) is a laboratory instrument, which measures the Tan Delta, Resistivity and Relative Permittivity of insulating liquids.  These tests give a wider picture of the overall quality of the insulating oil, and will indicate if there is any contamination. Megger has developed features of the OTD to ensure that productivity levels within laboratories are maximised.
The microprocessor controlled inductive heater means that there is uniformity of temperature throughout the cell, in compliance with IEC 60247, and for cooling a fan effectively speeds up the cell cooling time.  The instrument has a temperature measuring range of 10 to 110 ºC, with an accuracy of ± 1 ºC. It can be set to preheat before testing takes place. The automated oil drain facility negates the need to move the oil vessel.

User safety is paramount and with this in mind, Megger have designed independent and dual redundant high voltage cut-off circuitry. If for any reason the user needs to abort the test, this can be done so by pressing any key, immediately terminating the test and removing the high voltage.

The design of the cell components maximise oil fill rate but minimise turbulence in oil flow and eliminate trapping of air.  With only 32 cell components, it is easy to assemble and disassemble.

With the calibration checker, you can carry out a quick measurement check to validate Tan Delta, Resistivity and Permittivity measurements. An on-site service with an Approved Service Centre for calibration provides the opportunity to adjust measurements where necessary and minimise downtime.

OTD test sets are supplied with sixteen standard test sequences pre-installed, to support a set of international standards.

  • IEC 60247:2004;
  • IEC 61620:1998;
  • ASTM D924-08;
  • ASTM D1169:2002;
  • BS 5737:1979;
  • JIS C2101:1999;
  • VDE 0380-2:2005_01;
  • IS 6262:1971;
  • IS 6103:1971;

The instrument can also store up to 6 additional user-defined custom test sequences. Megger’s asset and data management software, Power DB Lite, is bundled at no extra cost providing an excellent tool for downloading and printing results.

With an easy to use interface, fast tabular navigation and quick text input via a telephone-style keypad, using the unit is incredibly easy.