I. Classification of Relay Protection Testers
Based on technical principles, output characteristics, and portability, they are mainly classified as follows:
(1) Classification by Technical Development and Output Waveform
Intelligent type (microcomputer/digital)
Characteristics: Controlled by DSP + FPGA or ARM, with pure sine wave output, high precision, stable small signal output, and support for GPS/Beidou synchronization.
Product status: Currently the mainstream product in the market.
Application scenarios: Debugging of smart substations and digital substations.
Conventional type (power frequency/analog)
Characteristics: Based on the principle of voltage regulators and phase shifters, large in size, low in precision, and largely phased out.
Transistor/integrated circuit type
Characteristics: Early products, with single functions, mainly used for calibrating electromagnetic relays.
Relay protection comprehensive tester
(2) Classification by Physical Structure and Portability
Handheld
Characteristics: Compact and lightweight, battery-powered, with relatively simplified functions, mainly for single-phase or simple three-phase testing.
Application scenarios: Inspection, on-site rapid troubleshooting, and simple overcurrent relay testing.
Portable
Characteristics: High integration, weighing around 10-20kg, the most widely used type.
Application scenarios: On-site debugging and preventive tests in most substations.
Desktop/rack-mounted
Characteristics: High power, multiple channels, full functions, usually placed in laboratories or maintenance centers.
Application scenarios: Factory tests, research and development verification, and teaching and training.
(3) Classification by Output Channels and Functions
Single-phase relay protection tester
Can only output single-phase or split-phase voltage and current simultaneously, mainly used for testing single voltage and current relays.
Three-phase/six-phase relay protection tester
Standard configuration includes four-phase voltage (Ua, Ub, Uc, Ux) and three-phase current (Ia, Ib, Ic).
Six-phase/twelve-phase tester: With multi-channel current output capability (six-phase current), mainly used for differential protection testing, capable of simultaneously applying current to the high-voltage and low-voltage sides.
Specialized testers
Including transformer testers, specifically for testing CT/PT volt-ampere characteristics and ratios; DC system testers; GPS synchronization testers, used for line longitudinal protection coordination.
II. Main Application Scenarios
Relay protection testers are involved throughout the entire life cycle management of power equipment, with main application scenarios including:
Infrastructure installation and commissioning
Before the operation of a new substation, all protection devices are subjected to power-on simulation tests to verify the correctness of settings, logic circuits, and trip/close circuits.
Preventive tests/regular maintenance
After 1-6 years of operation of power grid equipment, protection devices are calibrated for accuracy and action values as per regulations.
Fault investigation and analysis
After a power grid accident, fault quantities are simulated and replayed to check if protection devices have malfunctioned or failed to act.
Protection device technical transformation
After replacing new protection devices, simulation verification is conducted before load tests and vector checks.
Teaching and training
Used in power colleges and internal enterprise training to simulate various fault types such as single-phase grounding, interphase short circuits, and conversion faults in power systems.
Post time: Mar-03-2026