Handheld Relay Protection Tester

The MOEORW-TM315 is a handheld relay protection tester purpose-built for power system secondary operation and maintenance field work. Integrating advanced digital electronics and power amplifier modules with a high-capacity lithium battery, it condenses the performance of traditional benchtop testers into a handheld device weighing just 4.3kg. Whether calibrating protection relays for 110kV and above transmission networks or commissioning FTU, DTU, and TTU terminals in distribution networks, this portable three-phase relay protection test set delivers laboratory-grade accuracy with field-proven reliability.

Full-Range High Accuracy Output
Conventional handheld devices often meet accuracy specifications only at rated points, with errors increasing sharply at small signals or full load. The TM315 employs high-precision D/A conversion and closed-loop negative feedback technology to ensure consistent accuracy across the entire range-from minimal signals to rated full scale-with smooth, undistorted waveforms.
AC current full-range accuracy: ±0.1% ± 2mA (0.5A~15A); AC voltage full-range accuracy: ±0.1% ± 2mV (2V~130V). Output waveform total harmonic distortion (THD): ≤0.2%; rise/fall time: <100µs.
Whether testing minor fault quantities or severe short-circuit currents, this handheld three-phase relay protection debugger faithfully reproduces fault waveforms, eliminating protection setting misjudgments caused by tester errors.
 

High-Power Driving Capability and High-Current Output
Field wiring resistance and long test cables consume output energy. If the tester lacks sufficient driving capability, the actual value reaching the protection relay's sampling input will fall far below the set value, leading to completely erroneous test conclusions. The TM315 incorporates high-fidelity linear power amplifier modules to ensure output does not droop under real-world loads.
Current driving capability: ≥60VA/phase; Voltage driving capability: ≥30VA/phase. High-current output duration limits: 15A for 10 seconds, 10A for 20 seconds, 5A for 90 seconds, 3A continuous.
When testing overcurrent settings or performing complete group trip tests, this handheld relay protection calibrator delivers sufficient stable power to genuinely drive protection relays into operation, avoiding maloperation or failure-to-trip risks caused by insufficient output capability.
 

Low-Temperature Charge Protection and Extended Battery Life
Lithium battery internal resistance increases at low temperatures; charging under such conditions causes irreversible capacity degradation and even safety hazards. The TM315 incorporates an intelligent Battery Management System (BMS) that automatically suspends charging when the device temperature drops below 4°C and resumes only after the unit warms up, significantly extending overall battery pack lifespan.
Built-in 19.8AH ternary lithium battery pack provides over 8 hours of continuous operation under standard conditions. Operating ambient temperature: -10°C to +45°C, covering the vast majority of outdoor work scenarios.
On winter job sites in northern regions, many testers become inoperable due to low-temperature charging lockout. The intelligent thermal management strategy of this handheld three-phase relay tester ensures you can complete assignments even in freezing conditions.
 

Full-Function Software as Standard-One Unit Covers Both Transmission and Distribution Networks
No paid optional software modules. The TM315 comes preloaded with a complete suite of general test and functional test applications, covering everything from basic manual test, state sequence, AC sampling, relay test, and harmonic analysis, to advanced composite voltage overcurrent, distance protection, zero-sequence protection, under-frequency load shedding, undervoltage test, and synchronization test. It also supports superposition of up to the 20th harmonic, with frequency output ranging from 10 to 1000Hz.
A single unit simultaneously fulfills test requirements for transmission substations (distance/zero-sequence protection) and distribution automation terminals (FTU/DTU accuracy verification). No additional software license purchases are required, resulting in zero post-deployment usage costs-a critical factor in significantly reducing total cost of ownership for large-volume procurements.
 

Multiple Hardware Protections-Dual Safety for Equipment Under Test and Tester
Wiring errors in the field are inevitable. The TM315 incorporates hardware-level automatic detection circuits for voltage short circuits and current open circuits. Upon detecting abnormal load conditions, it instantly activates overload protection and automatically blocks output, while simultaneously displaying alarm messages on the screen.
Even if operators mistakenly open current circuits or short voltage circuits, this handheld relay protection tester will cut off output within milliseconds, safeguarding expensive substation secondary equipment and the tester's own amplifier modules from burnout.

Transmission Substation Protection Relay Calibration
Suitable for on-site periodic verification of line protection, busbar protection, and transformer protection in 110kV, 220kV and above substations. Typical applications include: distance protection impedance operating value and operating time testing, zero-sequence protection setting verification, reclosing and post-acceleration complete group trip tests, and under-frequency load shedding operating frequency and slip-blocking tests.

Distribution Automation Terminal (FTU/DTU/TTU) Commissioning
For pole-mounted switch controllers, station terminals, and distribution transformer terminals, performing AC sampling accuracy tests, telemetry/tele-signal point-to-point verification, overcurrent protection setting trigger tests, and operating time verification to ensure correct feeder fault handling in distribution automation systems.

Power Plant Auxiliary Power System Maintenance
In thermal, hydro, photovoltaic, and wind power plants, used for periodic pre-testing of auxiliary transformer protection, busbar protection, generator excitation system associated protections, and simulation testing of synchronizing equipment grid-connection conditions.

Factory Acceptance Testing for Protection Relay and Switchgear Manufacturers
As a supporting factory test tool for protection equipment manufacturers, used for production line functional verification, operating value calibration, and operating time measurement of batch-produced protection relays, ensuring every finished product meets quality standards before shipment.

On-Site Commissioning and Handover Acceptance for Power Engineering Companies
During the commissioning phase of new substations and retrofit/expansion projects, used for on-site protection setting verification, switch operating logic validation, and complete group trip tests with circuit breakers.

Industrial and Mining Enterprise Power Distribution System O&M
In steel mills, chemical plants, coal mines, and other high-energy-consuming enterprises, internal substations require periodic preventive testing of incoming protection, feeder protection, and motor comprehensive protection. The handheld portability of the TM315 makes it especially suitable for work in front of switchgear with limited space.

10-inch Industrial-Grade OLED Touchscreen: Eliminating traditional button-based operations, all parameter settings are performed via touch control. The screen layout is clearly partitioned: parameter editing area on the left, result display area on the right, and output control with status indicators at the bottom. RUN, ALARM, 4G, and WiFi status indicators are located at the top-right of the front panel, providing instant visual feedback on the instrument's current state.

Top Panel Layout: Adopts 4U+3I (4 voltage + 3 current) output terminals, compatible with both 3-phase 4-wire and 3-phase 3-wire connections. All voltage and current terminals use heavy-duty banana jacks that maintain reliable contact after repeated insertion and removal. The auxiliary DC output terminal provides DC 220V power externally, eliminating the need to carry a separate power supply for the protection relay under test.

Portable Design: With a thickness of just 80mm and weight of 4.3kg, it comes standard with a shockproof carrying case. A single person can carry it one-handed to any job site, significantly reducing the physical burden on field engineers-particularly suitable for substation inspection work requiring frequent relocation of test points.