Omega FLR 1000, Руководство пользователя

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To calculate the pressure drop at a certain flow rate use the formula
PD = (YourFlow / MaxFlow)
2
x
PD
max
PD = Pressure drop at YourFlow.
YourFLow = flow rate (ml/min or l/min)
MaxFlow = 100% rated flow for the sensor (in same units as YourFlow)
PD
max
= Pressure drop at 100% rated flow (see chart above)
If the pressure available for the flow sensor is BELOW the pressure drop at
the required flow then flow through the unit will not be possible.
For example: You have a sensor with a 50-500ml/min flow range and want
to know the pressure drop (or minimum differential pressure required) at
300ml/min. According to the chart above, the pressure drop at 100% of
flow is approx 10psi. Using the formula above:
PD = (300 / 500)
2
x 10 = 3.6 psid
Therefore, at 300ml/min the minimum required differential pressure for
this unit is 3.6 psid. This means that if the available pressure is below
3.6psid then flow through the unit may not be possible.
Pressure drop through a system is cumulative. If the total pressure drop
across all the components in a system exceeds the minimum pressure
available then flow will not be possible.
For example: A system has a pressure of 30-40psi. There are several
components and the sum of their pressure drops at the required flow rate
is 32psid. If the system is operating at 30psi flow would not be possible as
the total of the pressure drops would be greater than the pressure
available. The system will only operate if the system pressure is above
32psi.
If there is any possibility that there may be bubbles or entrapped gas in
the system then the outlet tubing should be elevated above the inlet port.
This will enable any gas that may become entrapped in the unit to escape
(see section C2 for details of how to remove entrapped air or gas).
2. Mounting the Flow Sensor or Flow Meter.
The Omega Engineering FLR 1000 Series units have no particular
installation requirements so may be mounted in any convenient position.
It is recommended that units be fixed to a suitable substrate with #4
screws using the two mounting holes provided.