The GCT2000 High-Precision Time Tester (the GCT2000) is a high-precision measurement device jointly developed by Guangdong Electric Power Research Institute and Shenzhen Shuanghe. Specially designed for the power industry, it uses double time reference sources of GPS and Beidou and has a built-in high-precision OCXO oscillator or a rubidium clock for timekeeping, thus guaranteeing its timing precision.

? Beidou + GPS mode, which makes it independent of GPS in terms of time reference sources and thus improves reliability and credibility.
? Built-in high-precision OCXO oscillator (with a daily aging rate of 3×10E-10) or a rubidium clock (1.2×10E-11). Incorporating the high-precision phase lock technique, it achieves a  precision of 30ns relative to UTC. Its resolution level for time measurement is 10ns.
? High reliability. The device adopts lithium batteries as its power supplies. When the batteries are charged, the device can work under a high-performance timekeeping algorithm for four hours in a row without reference sources so that it can adapt to special scenarios.
? With a time service optimization design specially made for the power industry, the device can test various time service signals, including 1PPS, 1PPM, IRIG-B (DC), IRIG-B (AC), NTP, and 10MHZ.
? Simple and easy-to-use interfaces. The same interface can, according to the interface setting, measure TTL, RS485/RS422 differential, idle contact, and similar signals.
? As the device provides time signal output of multiple standards, it can serve as a standard reference source for establishing a testing platform.
? A large 240×128 LCD display unit together with a 19-key keyboard, which is all-Chinese and has a friendly man-machine interface.

    The device can be applied at various research institutes of the power industry, the relay protection and automation departments of power supply bureaus, and enterprises involved in relevant research. It is used for measuring the output time indicator of time synchronization equipment in the power industry and the time service for timed equipment, and establishing the time test platform.