• Solutions
    • Outage Prediction
    • Wildfire Risk Mitigation
    • Underground Monitoring
    • Grid Edge Control
    • Harmonics Measurement
    • Fault Detection & Location
    • System & Asset Monitoring
    • Public Power
  • Products
    • Advanced Applications & Analytics ›
    • Overhead Line Sensors ›
    • Underground Line Sensors ›
    • Dynamic VAR Compensator
    • Professional Services ›
    • Grid Analytics System
    • Ample Analytics
    • Grid Analytics System
    • Ample Analytics
    • MM3ai System
    • MM3 Line Sensor
    • ZM1 Line Sensor
    • MM3ai System
    • MM3 Line Sensor
    • ZM1 Line Sensor
    • UM3 Line Monitor
    • UM1 Line Sensor
    • UM3 Line Monitor
    • UM1 Line Sensor
    • VC10 and Ample
    • VC10 and Ample
    • Engineering Services
    • MM3 Fault Indicator
    • Engineering Services
    • MM3 Fault Indicator
  • Resources
    • Use Cases & Case Studies ›
    • White Papers
    • Datasheets
    • Webinars
    • Use Cases
    • Customer Stories
    • Use Cases
    • Customer Stories
  • About Us
    • Events
    • Press and News
    • Careers
    • AWS Partnership
    • Blog Overview
Contact Us

Home › Products › UM3+ Underground Line Sensor

UM3+ UNDERGROUND LINE SENSOR

Increase Visibility of Underground Feeders

Sentient Energy’s UM3+ underground line sensor is an intelligent line sensor used to help utilities improve reliability. It captures and transmits accurate fault, disturbance, and load data from locations along underground feeders.

Download Data Sheet
Descargar En Espanol
sentient-energy-sentient um3 image 1

The UM3+ is a crucial element of Sentient Energy’s Grid Analytics System™. This system provides utilities with increased distribution system visibility to improve reliability and enable data-driven operational decision making.

This system consists of the MM3, MM3ai and ZM1 overhead line sensors, UM3+ and UM1 underground sensors, and the Ample® Analytics Platform.

UM3+ Underground Line Sensor Features

Powerful Sensing Capabilities

Sensing and measurement capabilities for the UM3+ include:

  • Underground fault detection
  • Highly accurate load and fault magnitude
  • Waveform capture
  • Equipped with GPS for location
  • GPS / PPS-level precision clock for highly accurate time-stamping (thereby allowing collating waveforms with those from other devices to perform a thorough post-even analysis).

High Deployment Versatility

The UM3+ is offered in two form factors to support a range of installation types: 

  • The UM3+ Standard supports monitoring of up to 12 phases and can be installed in larger footprint equipment such as switch cabinets and above grade vaults. 
  • The UM3+ Compact fits in smaller enclosures such as junction boxes and is also submersible for use in manholes and below grade vaults.

Advanced Network Communications

Communications networks supported by the UM3+ include cellular, mesh, and a combination of both. The sensor is wirelessly configurable, allowing parameters to be adjusted as needed. Users can also streamline sensor management by remotely updating sensor configurations and firmware.

UM3+ Underground Line Sensor Applications

Underground Fault Detection and Location

The UM3+ Underground Line Sensor uses advanced algorithms to sense system faults on underground lines in real time, communicating fault information immediately to the utility control center for integration with SCADA, DMS, or OMS systems.

With more precise fault location information, operators can dispatch crews to the correct location, significantly reducing patrol time and outage duration.

Person in a hard hat working on underground lines.
Green metal housing for UM3 line monitor and lines.

Interruption & Disturbance Analysis

Equipped with high resolution waveform capture capability at a rate of 256 samples per cycle, the UM3+ captures and records waveforms of faults and line disturbances.

Complete waveform data for faults is immediately available in Ample, and waveform data for disturbances is stored locally on the UM3+ and is available to download to Ample analytics software when needed. Understanding the root causes of power system interruptions essential for improving distribution grid reliability.

Load Monitoring

System planning teams don’t always have load data for the locations they need to make the most effective planning decisions. This is especially important as DERs and EVs are increasingly added to power networks creating significant changes in historic load curves and making load forecasting much more complex. Not all substations are equipped to provide near real time loading information and those that are cannot provide granular enough actionable data. Visibility of system load at additional points along underground feeders by UM3+ line sensors can fill in data gaps and be used to refine the accuracy of network load flow models.

Screenshot of graphs showing load current.

Check Out Our Underground Line Sensing Value Calculator

Learn More

Three Ways to Power the UM3+

UM3+ Powering Options Image 3 Phases 6 Phases 9 Phases 12 Phases
1. Single harvest core sentient-energy-Single Harvest Core transparent
12-14A
17-19A
19-21A
20-22A
2. Two harvest cores with Y cable adapter sentient-energy-Dual Harvest Core transparent
8-9A
10-11A
11-12A
11-12A
3. 100-240V AC Adapter 120-240V AC Adaptor
Power directly from AC

UM3+ Proven Field Deployments

Sentient 1
Sentient 2
Sentient 3
Sentient 4
Sentient 5
Sentient 6
Sentient 7

Ready for Better Underground Visibility?

Have questions about Sentient Energy products and solutions? Please contact us! Our support professionals are ready to provide the answers you need.

Contact Us
Sentient Energy | Enabling the Energy Transition

We help utilities deliver safe, reliable and efficient power.

Copyright © 2009–2025 Sentient Energy, Inc. All rights reserved | Privacy Policy
Contact Us

Solutions

Resources

Twitter Linkedin
  • Solutions
    • Outage Prediction
    • Wildfire Risk Mitigation
    • Underground Monitoring
    • Grid Edge Control
    • Harmonics Measurement
    • Fault Detection Location
    • System & Asset Monitoring
    • Public Power
  • Products
    • Advanced Applications & Analytics
      • Grid Analytics System
      • Ample Analytics
    • Overhead Line Sensors
      • MM3ai System
      • MM3 Line Sensor
      • ZM1 Line Sensor
    • Underground Line Sensors
      • UM3 Line Monitor
      • UM1 Line Sensor
    • Dynamic VAR Compensator
      • VC10 and Ample
    • Engineering Services
      • Engineering Services
      • MM3 Fault Indicator
  • Customer Success
  • Resources
    • Use Cases & Case Studies
    • White Papers
    • Datasheets
    • Webinars
  • About Us
    • Events
    • Press
    • Careers
    • AWS Partnership
    • Blog Overview
Contact Us
Follow Along:
Twitter Linkedin