Digital Transformer Turns Ratiometers

Why Choose AEMC®  Instruments Digital Transformer Turns Ratiometers?

Operator Safety

AEMC®'s portable digital transformer ratiometers (DTR®) are designed with safety in mind for on-site testing of power transformers, VT/PTs, and current transformers CT turn ratios with easy setup. No calibration or balancing required.

  • Injects into primary, read the secondary – Safer for the operator
  • Stores your 10 most common transformer nameplate values – saves time and eliminates errors in testing
  • Adjustable display contrast and backlighting - provides clear reading in all lighting conditions
  • Polarized H and X input cable connectors – eliminates errors in set up
  • Intelligent battery charging – prevents over charging, extends battery life

Quick and Accurate Measurements

When connected to a non-energized transformer, AEMC Transformer Turns Ratiometers accurately measure primary to secondary turns ratio, while simultaneously displaying polarity, excitation current and % nameplate deviation.

Easy to Operate - Automatic Measurements

No user calibration, range selection, hand cranking, or tedious balancing is required.

At each measurement, our transformer ratiometers automatically self-calibrate and check for open windings/connections/circuit breakers, short circuits (excess excitation current), incorrect test lead placement, and reverse polarity.

Key Features (DTR® model 8510)

  • Ratio test results in less than 7 seconds
  • Smart/fast battery charger with universal input voltage (100-240V, 50-60Hz) charges batteries in less than 4 hours
  • Display warns of incorrect lead connection, reverse polarity, open and short circuits
  • Easy connection and test setup; no calibration or balancing required
  • Large dual display with adjustable contrast ensures clearer visibility in any lighting
  • Filter selection to improve test results in electrically noisy environments
  • Stores up to 10,000 test results in internal memory automatically or by user selection
  • Includes DataView® software for instrument configuration, data storage, analysis, and report generation


  • Power Transformers
  • Potential Transformers
  • Current Transformers

Expert Tech Support

AEMC® provides complete technical support through our technical hot line 800-945-2362 (ext.351), speak directly to one of our tech support team members today. Or e-mail your questions to our tech team.

Excellent Customer Service

Our knowledgeable and friendly service team provides the best support in the industry. We seek to understand your inquiry or feedback in a respectful and responsive way. Our goal at AEMC Instruments is to surpass your expectations.

Speak directly to one of our customer care team members today at 800-945-2362 (Ext. 361). Or e-mail your questions

Request a Demo

Have questions on how to use AEMC® Power Analyzers and Energy Loggers? We're happy to provide a demonstration with our technical experts. Contact us at (800) 343-1391 or email us at

Digital Transformer Turns Ratiometers

  • Digital Transformer Turns Ratiometer Model 8510

    Cat. #2136.50
    Primary to secondary turns ratio, Polarity, Excitation current, Automatic self-calibration
    Digital transformer turns ratiometer for on-site testing of power, potential, and current transformers. Measures primary to secondary turns ratio, polarity, and excitation current. Automatically self-calibrates and checks for open windings/connections/circuit breakers, short circuits (excess excitation current), incorrect test lead placement, and reverse polarity.

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