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Transmission Multi-Ranging Voltage Indicator

Introducing the MRVI for Transmission!

The TMRVI (model number PSC4033955) is a state of the art portable tool designed to use on voltages 1 kV to 765 kV to confirm whether a transmission high-voltage circuit (69 kV through 765 kV) and substation equipment are at rated voltage, have induced voltage, or are de-energized.

It also provides the user the ability to observe lower voltages that may be present due to induction or storm emergency situations. Please remember to test the line before you do anything else on the job.

As the only Bluetooth® indicator on the market, the TMRVI sends the information you need right to your smart device. Energized, de-energized, induced voltage or any other quagmire on the line becomes much clearer when read through the TMRVI.

For safety, the Transmission Crews need to know the approximate induced (or storm damage connected) voltage present on the transmission conductors before they attempt to connect grounds.

Transmission Safety Solutions

Until this state-of-the-art unit came out, lineman had to contend with taking readings from a voltage detector on the end of long hot sticks, day or night, even in stormy, windy weather.

Do these lineman problems sound familiar?

  • You need a better solution than just shouting the readings to another crewman on the ground.
  • You’re tired of trying to read the tiny needle on the face of a voltage detector.
  • You wish there was a remote readable display NOT attached to the voltage detector.
  • You’re having to use a switch or other methods to choosing the correct setting prior to line contact.
  • You’re having to read the right scale out of multiple scales, adjusting for voltage differences, doing mental math, while always doing your best to stay safe.
  • You want to prove to the Dispatchers and Operations what you are seeing on the voltage detector. (Even after you have completed your job).

That’s why we created the Transmission MRVI and the Distribution MRVI! To deliver a clear picture of the voltage conditions on the line with a larger – and lighter – display. And with the added Bluetooth® capability, reading the situation has never been safer, more efficient or provable.


  • Meets the intent of OSHA 1910.269 to test for absence of nominal voltage
  • Used to determine if power lines are at rated voltage, have induced voltage, or are de-energized
  • For overhead and underground systems (with appropriate adapters and Hot Sticks)
  • Stepper motor technology
  • Illuminated fluorescent pointer
  • Power-saving sleep mode (auto-off)
  • Checks battery voltage on initial startup
  • Positive interface power button
  • Equivalent Phase-to-Phase and Phase-to-Ground reading ranges
  • Manually activated Hold Mode
  • Bluetooth® technology
  • New lightweight design (19.8 oz without batteries)
  • Battery drawer for simple battery replacement
  • Comes with a storage bag with a snap-hook designed to attach to a lineman’s belt
  • QR code located in the instructions, Quick Reference guide, and on the unit itself

Must be used with properly selected universal hot stick, even with rubber gloves.

Free APP for MRVI!

Our free app connects the MRVI to your smart device – even to an Apple watch! You get the information you need to do the job safely – right in your hand. You can even mark your location or email log history to yourself for later reference or proof of testing.


See your local Hubbell Distributor to purchase a Transmission Multi-Ranging Voltage Indicator!

Keep it safe out there.

    The distribution voltages on the left-hand side of the scale are for properly trained Transmission Linemen to detect distribution voltages on the “low side” of the substation transformer, voltage induction, or storm emergency damaged conductors that may be energizing the transmission system (even though it is de-energized from the source and but not yet grounded).
  • The TMRVI does not replace the Distribution MRVI (model number PSC4033710) which has Capacitive Test Point and lower voltage resolution. This transmission rated TMRVI begins at 1KV and goes up through 765kV AC.
  • The TMRVI meets the intent of OSHA 1910.269 to test for absence of nominal voltage. It provides field practicality over the two points of contact measurement method. Readings from the TMRVI represent the class of voltage that is present on the line. This unit is a direct contact electric field intensity indicator.
  • For safety, the use of the TMRVI requires the use an appropriate length insulated Hot Stick even when wearing rubber gloves. Minimum Approach Distances (MAD) should be adhered to at all times. For the latest information and charts, refer to the official OSHA website:
  • Before operating a Chance® Transmission Multi-Range Voltage Indicator (TMRVI), thoroughly read, understand and follow the provided instructions, which are also available through use of the following QR Code when connected to the internet.