# 2.4.3 Flight time

The seventh interface of the display output interface displays all values related to ultrasonic signal flight time (Time of Flight, or ToF). TOM (as shown in the picture) represents measured flight time, and TOS the calculated theoretical flight time. Ideally, the two values should be equal. If TOM/TOS yields a value that exceeds 100% ± 3%, the following steps should be taken: 

● Check if the relevant setting parameters are correct. Check pipe material, pipe diameter, whether there is a liner, fluid type, and other relevant parameters. Check to ensure that the probe is mounted correctly. 

● Check to ensure that the probe mounting distance is correct. 

If> 100%, adjust upstream and downstream probes and bring them closer together. 

If <100% adjust distance of probe, by moving them further apart.


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