TESCO® Metering today announced the launch of the 4E2-1 Third Rail Voltage Detector, a specialized safety instrument engineered to detect electrical potential between third rail systems and ground in high-voltage transit and utility environments. Designed for reliability, durability, and clear operator feedback, the 4E2-1 provides visual and audible voltage indication to support safer field operations.
As transit authorities and utilities operate within increasingly complex and high-voltage environments, ensuring technician safety during inspection, maintenance, and testing activities has become a critical priority. Third rail systems present unique hazards that require specialized detection tools capable of delivering clear, immediate confirmation of voltage presence. The 4E2-1 addresses this need by combining redundant detection circuits, high-visibility LED indicators, and an audible alarm within a rugged, field-ready design.
Purpose-Built for High-Voltage Detection and Operator SafetyThe 4E2-1 Third Rail Voltage Detector is engineered to safely detect electrical potential between third rail systems and ground in electrified transit applications. The device utilizes two independent circuits with redundant LED indicators to provide clear visual confirmation of voltage, while a built-in audible alarm delivers an additional layer of situational awareness for operators.
Designed for harsh field environments, the detector features a moisture- and oil-resistant phenolic handle and housing, sealed internal electronics, stainless steel prod tips, and an integrated rubber hand guard to promote safe handling and reliable performance.
Key Advantages for Transit and Utility ProfessionalsEnhanced safety through redundant detection: Dual circuits provide added confidence in voltage detection.
Visual and audible alerts: High-visibility LED indicators and an audible alarm ensure clear voltage confirmation in all lighting conditions.
High-voltage capability: Operates on AC or DC systems up to 1,500 volts.
Extended reach: Spans distances of up to four feet for safer testing proximity.
Rugged, field-ready construction: Phenolic housing, sealed electronics, and stainless steel tips ensure durability in demanding environments.
Proven transit application: Developed for and used by BART and other transit systems.
Supporting Safety in Critical Infrastructure EnvironmentsThe 4E2-1 is designed for use in electrified rail systems, transit maintenance operations, and high-voltage utility applications where accurate voltage detection is essential to personnel safety. Its combination of redundant detection, clear alerts, and rugged construction enables operators to verify voltage conditions quickly and confidently before performing work in hazardous environments.
“Working around high-voltage infrastructure leaves no margin for uncertainty,” said Tom Lawton, President & CEO of TESCO Metering. “The 4E2-1 was engineered to provide clear, reliable confirmation of voltage presence, helping transit and utility professionals make informed safety decisions before they begin work.”
Product Summary4E2-1 Third Rail Voltage Detector
Detects electrical potential between third rail and ground
Operates on AC or DC systems up to 1,500 volts
Dual detection circuits with high-visibility LED indicators
Built-in audible alarm for enhanced situational awareness
Rugged phenolic housing, sealed electronics, and stainless steel prod tips
Designed for high-voltage transit and utility environments
Since 1904, TESCO® Metering has been the trusted leader in American-made metering equipment and custom utility products for the electric utility industry. With over a century of engineering innovation, TESCO designs and manufactures precision meter testing instruments, field test kits, and smart grid metering solutions that ensure accuracy, reliability, and compliance across today's evolving energy infrastructure.
From our ISO 9001 and ISO 17025 certified facility in Bristol, Pennsylvania, TESCO proudly builds all products in the US, supporting domestic manufacturing, short lead times, and superior quality control. Our U.S.-manufactured metering systems serve utilities across North America, including meter test boards, burden sets, EVSE testers, optical probes, and custom field-testing equipment engineered for precision and durability.
TESCO's portfolio spans lab-grade testing setups, rugged field kits, and AMI test solutions designed to meet the demands of modern smart grid environments. What sets TESCO apart is our close collaboration with utility engineers, meter shop managers, and field technicians—developing custom metering tools that solve real-world challenges, improve safety, and streamline operations.
Beyond products, TESCO is deeply committed to metering education and industry training. Our annual TESCOOL event and support of regional meter schools reflect our dedication to advancing utility expertise and maintaining technical excellence across the metering community.
With generations of trust, TESCO Metering continues to lead in custom utility solutions, American-made metering equipment, and dependable technical support. Contact us to learn how TESCO's precision utility instruments can improve accuracy, safety, and efficiency for your metering operations.
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