How to Choose a Six Phase Relay Protection Tester?

Relay protection tester is a core tool in the field of relay protection, which can cost tens of thousands of yuan. Choosing the wrong one can be troublesome for several years. Clarify the several core dimensions that truly affect the user experience, and compare them to avoid making mistakes.

First: Six phase or three-phase

If the scope of work involves transformer differential protection, generator differential protection, backup automatic switching, and fast switching of plant power, six phases must be selected. The three-phase tester for differential testing requires repeated wire changes and calculation of compensation relationships, resulting in low efficiency and high error rates; Six phases can be connected in one go, and the difference is quite significant. If only line protection (distance, zero sequence, overcurrent) is used, three-phase is sufficient.

Secondly, amplifier type

Linear power amplifier (used by HZJB-1200): The output waveform is clean, with high precision throughout the entire process from high current to low current, without generating high-frequency interference, suitable for occasions with high requirements for waveform quality and testing accuracy; The cost is relatively high, with slightly larger volume and weight.

Switch type power amplifier: small in size, light in weight, low in cost, sufficient for daily overcurrent protection calibration, but inferior to linear power amplifiers in harmonic superposition testing and low current accuracy testing.

Thirdly, output range

Voltage: Maximum 120V per phase, line voltage 240V; fundamental frequency 0-1000Hz; harmonics 0-20th order - these three parameters determine how many protection types can be covered.

Current: Single phase maximum output 30A (standard 6-phase), parallel maximum 60A (3-phase) or 180A (6-phase). Fixed values beyond this range require additional consideration of wiring schemes.

Fourth: Time measurement accuracy

0.1ms accuracy is a basic requirement for relay protection testing. Most action time settings are accurate to 0.01 seconds, and insufficient measurement accuracy can lead to fuzzy criteria, especially when testing rapid protection (I-segment distance protection action time<20ms), if the accuracy is not poor enough by one or two milliseconds, misjudgment may occur.

Fifth: Test whether the module covers the requirements

20 modules cover almost all types of protection in the domestic power system. When selecting, check your own work scenario: whether there is a differential protection module (including proportional braking characteristic curve search), a synchronous test module, and a fault reproduction module. These three are the key to distinguishing between basic and professional types.

Sixth: Independent DC power supply

The HZJB-1200 has a built-in 110V/220V adjustable DC power output, which can directly supply power to the protection device when there is no DC screen on site. This function is very practical in old substations and temporary testing sites, avoiding the trouble of specifically pulling DC power.