Tecfluid CP CH420 Series, Инструкция по эксплуатации

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6 EXAMPLE OF USEFUL CALCULATIONS
The calibration of the flowmeters is made with water at 20ºC. If other characteristics from the
above specified are used or for reasons of turbulences in the flow, measurement errors can
be induced.
To correct these types of errors, the k (pulses per litre factor) programmed in the instrument
can be modified.
Example - Shortage of volume
If we have a converter which specifies a k factor = 1.985, and when we check the volume of
a batch, we find that instead of having 100 litres as programmed, we have 105 litres (5%
more), we must apply the following correction:
F
k
= k factor (original pulses per litre) = 1.985
V = Expected Volume = 100
Vr = Real Volume = 105
F
k
n = New k factor = ? (1.887)
Example - Excess of volume
If we have a converter which specifies a k factor = 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), we must apply the following correction:
F
k
= k factor (original pulses per litre) = 1.985
V = Expected Volume = 100
Vr = Real Volume = 95
F
k
n = New k factor = ? (2.089)
7 HART COMMUNICATION
The CH420 transmitters have a HART communication MODEM
The details of the characteristics with respect to the HART communication are available in
the appropriate “Field Device Specification”.
Resume of the principal communications characteristics:
Manufacturer, Model and Revision Tecfluid S.A., CH420L o R, Rev. 0
Device type Transmitter
Hart Revision 6.0
Device Description available No
Number and type of sensors 1, external
Number and type of actuators 0
Number and type of host side signals 1, 4 – 20 mA analog
Number of Device Variables 2
Number of Dynamic Variables 1
Mappable Dynamic Variables No