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TDS Rentals & Leasing is your One Stop Shop providing Doble products with Rental, Sales and Lease To Own options plus the benefit of our in-house calibration and repair.


817-465-9494 or email sales@tdsrl.com


doble M4100

Available Now:  Doble M4100 Power Factor Test Set

Call us at (817) 465-9494 or Email sales@tdsrl.com for more information!


Doble M4100 Equipment Specifications

The M4100 is the leading instrument for evaluating the condition of high-voltage power apparatus. It sets the standard for accuracy, reliable test results, and intelligent diagnostics for customers worldwide. The M4100 was engineered from the ground up to overcome the common problems that plague other test instruments.

With a maximum output of 300 mA at 10 kV, the M4100 offers high charging current, allowing you to run single-phase exciting current tests at higher voltages, increasing the turn-to-turn stress. The M4100 has the power to test a wide range of apparatus, making it highly versatile. If you need more current than 300 mA for large apparatus, the Type C Resonator option extends the range. If you need higher voltage than 12 kV, the M4120 External Reference Module option allows you to use a power supply other than Doble’s and adapt to any international standard.

The accuracy of test results is directly related to the quality of the test signal. While most test instruments use available power lines or portable generators to generate the output test signal, the M4100 uses an internal waveform generator to create its own precise sine wave. This produces reliable results and stable readings. The quality of the power source is not an issue.


  • Power Factor testing to confirm insulation integrity and quality
  • Capacitance testing to measure physical changes that may have occurred to the apparatus
  • Turns Ratio testing to detect shorted turns or winding damage
  • Leakage Reactance/Short Circuit Impedance testing to evaluate winding deformation
  • Single Phase Excitation Current testing to evaluate the transformer’s magnetizing circuit