The cause of crystal oscillator failure

Example: If the accuracy range of the crystal oscillator is 5PPM, then we can calculate the time of day error is: 5 (ppm) x24 (Hours) x60 (minutes) x60 (seconds) =432000*1/1000000=0.423s
That is, the daily error does not exceed 0.423 seconds.

RTU test real-time clock daily error requirements less than 4S. Measurements are fast and slow, fast to 10 seconds, and slow to 8 seconds. After taking to the sea-based electronic equipment test found that -60ppm to 78PPM are, discrete distribution. Crystal oscillator not conforming to requirements

The cause of crystal oscillator failure