Desin Instruments HS-7000 Series, Общее руководство по инструкции

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EXAMPLE 1: FLOW COMPENSATION
Conversion of a flowmeter expressed in imperial units (0-6000 gal/h) to metric units (0-22710
L/h), with a correction of the Lo-Range of the signal (200 gal/h = 757 L/h, but it is required
to indicate 930 L/h):
P03 P04 P05 P06 P07 P08 P09 P10 P11 P12
0 200 0 0 0 0 0 0 0 6000
P13 P14 P15 P16 P17 P18 P19 P20 P21 P22
0 930 0 0 0 0 0 0 0 22710
The intermediate points can be set to 0.
EXAMPLE 2: SQUARE ROOT EXTRACTION
Square root extraction of a 4-20mA signal with a range of 0-100%, of a DP transmitter for flow
measurement:
P03 P04 P05 P06 P07 P08 P09 P10 P11 P12
0 100 500 1000 2500 3000 5000 6000 7500 10000
P13 P14 P15 P16 P17 P18 P19 P20 P21 P22
0 1000 2236 3262 5000 5477 7071 7746 8660 10000
Select two decimal points ( 0,00 ) for both lista, in [P02].
To express the above example values in physical units, define the relation between % to physical
units and itroduce these values in ponts P03...P12 and P13...P22 of the above table.
EXAMPLE 3: TANK VOLUME MEASUREMENT
Linearization of the volume of a spherical tank with respect to its hydrostatic height 0 - 100%.
P03 P04 P05 P06 P07 P08 P09 P10 P11 P12
0 800 1200 1800 3300 6700 8200 8800 9200 10000
P13 P14 P15 P16 P17 P18 P19 P20 P21 P22
0 180 397 855 2548 7451 9144 9602 9818 10000
To express the above example values in physical units, define the relation between % to physical
units and itroduce these values in points P13...P22 of the above table. For example, if the
maximum capacity of the tank is 30000 L. calculate the value of each point P13...P22 as % of
the total Volume such as: 30000*P/10000, thus, multiplying by 3 each point P13...P22, the
result is:
P13 P14 P15 P16 P17 P18 P19 P20 P21 P22
0 540 1191 2565 7644 22353 27432 28806 29454 30000
In case of tanks with known volume (i.e. provided with cer tified capacity tables), linearize those
non-linear segments of the curve.
In case of ver y irregular tanks, it is recommended to draw the tank using a CAD software and
then calculate the volume of the tank in 10 levels, distributing the points in the most non-linear
segments. AThen, introduce the calculated values in points P03...P12 and P13...P22.
Linearization in 0 - 100% of a horizontal cylindrical tank with caps of R = D and R = 2*D
R=D P13 P14 P15 P16 P17 P18 P19 P20 P21 P22
0 358 662 1202 2864 7135 8798 9338 9641 10000
R=2D P13 P14 P15 P16 P17 P18 P19 P20 P21 P22
0 354 647 1172 2831 7168 8827 9353 9646 10000