Potential Transformers (PT) | Voltage Transformers for Metering & Protection

Products

Weatherproof PT Junction Box (Prefab) – Steel Construction – NEMA 3R Outdoor Rated

$2385.00

Weatherproof PT Junction Box (Prefab) – Three PT Capacity – Steel Construction – NEMA 3R Outdoor Rated

$3195.00

Weatherproof PT Junction Box (Prefab) – Three PT Capacity – Steel Construction – NEMA 3R Outdoor Rated

$3195.00

What Are Potential Transformers (PT)?

Potential Transformers (PT), sometimes called Voltage Transformers (VT), are precision devices used to reduce high system voltages to standardized secondary values for measurement and control. By electrically isolating instrumentation from primary conductors, PTs allow accurate voltage sensing while protecting personnel and sensitive equipment.

How Are Potential Transformers Used?

PTs are a foundational element of power monitoring and protection systems. They provide scaled voltage signals to meters, protective relays, and control devices, enabling operators to safely observe system conditions and respond to abnormal events. These transformers are commonly used wherever accurate voltage reference is required without direct connection to energized conductors.

Common Applications

Utility and industrial substations
Metal-clad and metal-enclosed switchgear
Medium-voltage distribution systems
Protective relaying and fault detection
SCADA and power monitoring systems
Critical facilities and data center infrastructure

Types of Potential Transformers

Type	Description	Typical Use
Electromagnetic PT	Iron-core design offering high accuracy and stability	Metering and protection circuits
Capacitive Voltage Transformer (CVT)	Capacitor-based design for higher voltage levels	Transmission and utility systems
Indoor PT	Designed for controlled environments	Switchgear rooms and panels
Outdoor PT	Weather-resistant construction	Substations and outdoor installations

Key Specifications to Consider

Primary Voltage Rating: Matched to system voltage
Secondary Voltage: Standard outputs for metering and relays
Accuracy Class: Determines suitability for metering or protection
Burden Rating: Load the PT can support without loss of accuracy
Insulation & BIL Rating: Protection against transient overvoltages

Why Potential Transformers Matter

Accurate voltage measurement is critical for system stability and protection. PTs enable protective relays to detect conditions such as undervoltage, overvoltage, phase imbalance, and loss of phase. Reliable voltage sensing helps prevent equipment damage, improve system diagnostics, and support safe operation across electrical distribution networks.

Why Choose Larson Electronics?

Larson Electronics supplies potential transformers built for dependable performance in demanding power environments. Our PT solutions are selected to meet the accuracy, insulation, and durability requirements of utility, industrial, and mission-critical applications. Backed by responsive technical support and fast quoting, Larson Electronics helps customers maintain safe, efficient, and well-monitored power systems.

For more information or assistance selecting the right potential transformer for your application, contact Larson Electronics. Larson Electronics – Building Trust Since 1973.