Although the flow meter was set zero before leaving the factory, it may be offset because of the inevitable slight impact on transport. If the flow meter does not display zero when the flow velocity is zero, zero offsets occur and zero set operation has to be done:
- Close the behind valve.
- Turn on the front valve slowly, make the tube fill measured medium.
- Turn on the flow meter and run for about 5 minutes under max instantaneous flow condition.
- Close the front and behind valves and make sure that the flow velocity is zero.
- Do zero set operation according to the following set instruction.
- For the high-temperature flow meter without temperature compensation, zero set operation is necessary while running for each period of time.
- For the high-temperature flow meter with temperature compensation, zero set operation has to been done in normal but high-temperature conditions.
- For the flow meter with pressure compensation, the pressure zero is also needed to be set according to the following set instruction.