Omega FLR 1000, Руководство пользователя

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a) Flows Above the Maximum Rated Flow.
If the flow rate is above the maximum rated (or full scale) flow, the unit
will still operate and provide an output signal proportional to the flow rate.
Flows must not exceed 120% of the maximum rated flow or the unit may
be damaged.
b) Flows Below the Minimum Rated Flow.
Signal outputs may be obtained at flow rates below the minimum specified
for your unit. The amount of flow that may be measured below the
minimum specified varies from unit to unit.
5. Zero Adjustments
It is impossible for there to be any zero drift so zero adjustments are
never required.
6. Recalibration
The calibration of the unit may be easily verified using empirical methods.
It should be noted that the use of empirical methods outside a certified
calibration laboratory is subject to inaccuracy and error. These methods
should only be used to gain an indication of a sensor’s performance.
Please contact the Omega Engineering Service Department if accurate,
certified recalibration is required.
A typical empirical calibration check may be carried out as follows:
Carefully adjust the flow rate so that the maximum output signal is
obtained. With the flow rate constant, liquid flowing through the unit
should be gathered in a container over a timed interval. The total volume
flowed over the timed period should then be measured using a measuring
cylinder. The actual flow rate (in the same units as the flow sensor
calibration certificate) may then be calculated. The actual maximum flow
rate should then be compared to the specified maximum flow rate to
determine the error in calibration. For example:
For a unit with a flow range of 20-200ml/min and a 0-5VDC
output:
With a constant flow and constant 5VDC output the actual
volume measured over 30 seconds was 102ml.
Therefore the actual flow rate is:
(102 / 30) x 60 = 204ml/min
The error is therefore 204 – 200 = 4ml/min or 2%