Titan Metraflow 240-020, Instruction Manual

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©Titan Enterprises Ltd 2018 www.flowmeters.co.uk MetraflowManual_v1219
Gas Entrainment or Modulating Fluids
Fluids which entrap gasses or seriously modulate the ultrasound will cause problems with the time of
flight measurement. This might include viscous fluids being re-circulated from a small volume
reservoir or Glycol type fluids.
Gasses seriously affect the ultrasound and should be avoided. It is recommended that the meter is
always installed in a positive pressure system with a back pressure of at least 0.5 Bar plus 2 times the
fluid vapour pressure. It is preferable to install the meter in a way that any trapped vapour can escape
the flow measurement section. i.e. in a vertical line with the flow upwards.
The meters are calibrated on water at ambient temperature typically 21 to 25°C.