2.3. Reset
By pushing the RESET push button, the counter will be set to zero and it will continue to
count .
3. MAINTENANCE
It doesn’t require any special maintenance.
4. MEASUREMENT ERROR CORRECTIONS
The calibration of the mechanical flow meters is made with water at 20
o
C to obtain a
calibration for a liquid of density 1 kg/l and viscosity of 1 mPa·s. If the flow meter is used with
a liquid of other characteristics from the above specified or for reasons of turbulences in the
flow, measurement errors can be induced.
To correct these types of errors we can modify the pulses per litre factor programmed in the
instrument.
Example 1 - Shortage of volume
If we have a flow meter body which specifies i/l = 1.985, and when we check the volume of a
batch, we find that instead of having 100 litres as programmed, we only have 95 litres (5%
less) and we must apply the following correction:
i/l = Original Pulses per litre Factor
= 1.985
V = Expected Volume
= 100
Vr = Real Volume
= 95
i/l n = i/l
V
Vr
i/l n = New Pulses per litre Factor
= ? (2.089)
Example 2 - Excess of volume
If we have a flow meter body which specifies i/l = 1.985, and when we check the volume of a
batch, we find that instead of having 100 litres as programmed, we only have 105 litres (5%
more) and we must apply the following correction:
i/l = Original Pulses per litre Factor
= 1.985
V = Expected Volume
= 100
Vr = Real Volume
= 105
i/l n = i/l
V
Vr
i/l n = New Pulses per litre Factor
= ? (1.887)
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