High Precision Relay Protection Tester

S903 is an industrial control type three-phase relay protection tester for 10KV/35KV and below protection debugging. It features four-phase voltage and three-phase current output, 10.4-inch true color display, independent DC auxiliary voltage source, 8 pairs of digital input and 4 pairs of digital output terminals, and software self-calibration function. With compact size and easy operation, it is suitable for testing traditional relays and modern microcomputer protection devices.

The S903 microcomputer Relay Protection Tester-a professional 3 phase secondary injection test set and high-performance relay tester-is a dedicated testing device for power system relay protection debugging, built with a high-performance embedded industrial control computer and a 10.4-inch true color display. It supports standard four-phase voltage and three-phase current output, capable of testing various traditional relays and microcomputer protection devices, especially convenient for transformer differential protection and automatic bus transfer device tests.The tester is equipped with 8 pairs of optically isolated digital input terminals and 4 pairs of digital output terminals, an independent DC auxiliary voltage source (110V/1A, 220V/0.6A), and dual USB interfaces for easy data access and software upgrade. Its built-in software self-calibration function ensures high precision stability without manual potentiometer adjustment.With excellent technical parameters, it has high output accuracy (AC current/voltage 0.2% precision), wide frequency range (0-1000Hz), and supports 2-20 harmonic output. The compact body (328×168×250mm) and humanized panel design (touchpad, shortcut keys, anti-collision corners) make it easy for on-site operation, an essential tool for 10KV/35KV power system protection debugging.