The Best Secondary Injection Electrical Relay Test Kits for Reliable Protection

Secondary injection testing is a cornerstone procedure for verifying the reliable operation of protection relays by injecting controlled current and voltage signals into relay secondary circuits. This method avoids the risks of testing on the primary high-voltage side and provides precise assessments of relay functionality, timing, and settings.

What to Look for in a Secondary Injection Test Kit?

An ideal secondary injection relay test kit should have the following features:

• High accuracy in current and voltage injection over wide ranges

• Multiple independent current and voltage channels

• Compatibility with both electromechanical and modern digital relays

• Support for relevant protocols like IEC 61850

• Portability and ruggedness for field use

• Intuitive operation with PC/tablet software for automation and data analysis

• Advanced functions like timing, phase shifting, harmonic analysis, and fault simulation

Leading Secondary Injection Test Kits in 2025

Brand & Model	Key Features	Best For
Omicron CMC 356	Six current sources (up to 64 A per channel), four voltage outputs, IEC 61850 support, advanced automation (Test Universe software), robust and versatile	Utilities, industrial and lab testing for all relay types, including high-burden electro-mechanical relays
Megger FREJA 546/543/549	4 voltage & 3 current channels (up to 60 A/300 VA/phase or up to 9 currents for 549), convertible outputs, high-res touchscreen, PC/manual, IEC 61850; GPS sync end-to-end testing	Field & Lab testing for all relay types
Megger FREJA 300	ightweight (15 kg), portable, 3 current & 4 voltage channels, versatile, PC or standalone	Simple & General field use
Megger SVERKER 900 Expert	Three current, four voltage outputs, full three-phase testing, standalone operation, rugged design, user-friendly touchscreen UI	Complex substation testing, industrial relay testing including digital and electromechanical relays
Megger SMRT410 / SMRT410D	Lightweight, portable, multipurpose with 4 voltage and 6 current channels, manual and automatic test modes	On-site testing, mid-level relay maintenance and commissioning
Megger SVERKER 780	Designed for single-phase relay testing, output up to 100 A, adjustable frequency and phase shift	Single-phase protective relay testing in industrial environments
Megger SVERKER 650	Single-phase output up to 100 A, durable field use equipment, accurate and reliable	Rugged field relay testing for protection relays
Kingsine K3040	Wide voltage/current range, self-protection, PC software integration, energy-efficient	General field testing with focus on energy meter and transducer compatibility
Motwane RTS Series	Portable, cost-effective, effective for voltage and current relay testing	Basic onsite relay testing
SMC Quasar and PTE Series	Three-phase outputs, compact design, Wi-Fi connectivity, support IEC 61850	Advanced industrial and substation maintenance and testing
T&R Test Equipment Sets	Output current up to 200 A, voltage up to 240 V, timing and phase shift analysis, memory storage	Advanced diagnostics and relay analysis

In-Depth on Top Picks

Omicron CMC 356:

• The universal solution with six independent current outputs capable of delivering up to 64 A per phase (860 VA), ideal for testing high-burden electromechanical relays as well as today’s digital relays.

• Supports IEC 61850 communication protocols, GOOSE simulation, Sampled Values, and SCADA communications.

• Offers extensive test automation with Omicron’s Test Universe software, including state sequencing, harmonic analysis, and power-quality tests.

• Rugged design, with multiple connectivity options (Ethernet, USB, Wifi), and additional features like 10-channel analog measurement and transient recording.

• Widely praised for accuracy, robustness (e.g., can withstand rough handling), and versatility for field and lab use.

Megger FREJA Series:

Megger FREJA 546/FREJA 543:

• 4 voltage and 3 current channels (convertible to provide up to 6 current channels)

• High current output: up to 60 A / 300 VA rms per phase

• Standalone touchscreen interface—no PC required (FREJA Local software)

• Fully automated PC-based testing (FREJA Win/Remote software)

• Built-in preset routines, robust data storage and export, easy report generation

• GPS-synchronized dynamic end-to-end testing

• IEC 61850 testing and daisy-chaining for large bus or differential schemes

• Portable and rugged, suitable for any

Megger FREJA 549

• Up to 9 current channels for complex multi-phase schemes

• Programmable outputs to simulate circuit breaker operation

• Audible/visual error alarms for test security

• All features of 546/543, plus expanded multi-channel capability for large system applications

FREJA 300:

• Compact and rugged, optimized for portability

• 3 current & 4 voltage channels, accurate and reliable

• Manual or PC-driven testing with broad protection relay compatibility

Megger SVERKER 900 Expert:

• Features three current and four voltage outputs enabling full three-phase testing in a portable, rugged box with intuitive touchscreen interface.

• Supports stand-alone operation without the need for an external PC, ideal for industrial and substation relay testing.

• Offers a rich set of measurements including ammeter, voltmeter, power factor, impedance, and frequency, making it highly versatile.

• Proven reliability and ergonomics suitable for challenging field conditions.

Megger SMRT410 / SMRT410D:

• Lightweight and portable with a combination of voltage and current channels tailored for various relay types.

• Supports both manual and automated testing, with advanced software to assist in detailed relay evaluation.

Megger SVERKER 780 and 650:

• Focused on single-phase testing applications, offering high current output (up to 200 A) and variable frequency and phase shift capabilities.

• Rugged, compact, and field-friendly models optimized for certain relay types and easy transport.

Why Secondary Injection Testing Matters

• Tests relay pick-up, timing, and configuration by simulating fault conditions safely on the secondary side of protection circuits.

• Avoids disconnecting or interrupting the primary power system, enhancing safety for both personnel and equipment.

• Enables verification of relay functionality before commissioning or routine maintenance, ensuring system protection integrity.

Investing in a top-tier secondary injection test kit such as the Omicron CMC 356 or Megger Freja, Megger SVERKER 900 Expert delivers the highest levels of accuracy, power, and flexibility for all relay testing needs. Complementary models from Megger, Kingsine, Motwane, SMC, and T&R offer options tailored to various testing environments and budgets.