1. Environment:Finder relayThe mean time between failures (MTBF) operating in GB and SF is 820000 hours, while it is only 60000 hours in Nu environment.

2. Quality level: the average time between failures of finder relay with A1 quality level is 3660000h, while the average time between failures of finder relay with C quality level is 100, with a difference of 33 times. It can be seen that the quality level of finder relay has a great impact on its reliability.

3. Contact form: the contact form of finder relay will also affect its reliability. The reliability of single throw relay with the same number of poles is higher than that of double throw relay. With the increase of the number of poles, the reliability gradually decreases. The average fault interval time of single pole single throw relay is 5.5 times that of four pole double throw relay.

4. Structure type: there are 24 types of finder relay structure, and different types will affect its reliability.

5. Temperature: the working temperature range of finder relay is -250 ℃ ~70 ℃. With the increase of temperature, the mean time between failures of finder relay decreases gradually.

6. Action rate: as the action rate of finder relay increases, the mean time between failures basically shows an exponential downward trend. Therefore, if the designed circuit requires the finder relay to operate at a high speed, it is necessary to carefully check the finder relay in order to replace it in time when the circuit is repaired.

7. Current ratio: the so-called current ratio is the ratio of the working load current of the finder relay to the rated load current. The current ratio has a great influence on the reliability of finder relay, especially when the current ratio is greater than 0.1, the mean time between failures decreases rapidly, while when the current ratio is less than 0.1, the mean time between failures is basically unchanged. Therefore, in the circuit design, the load with larger rated current should be selected to reduce the current ratio, so as to ensure that the reliability of finder relay or the whole circuit will not be reduced due to the fluctuation of working current.