Siemens HydroRanger 200 HMI, Руководство по эксплуатации

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Technical reference
A.8 Scanning
HydroRanger 200 HMI
Operating Instructions, 06/2018, A5E36281317-AC
307
A.8 Scanning
The device
When echo processing is complete (if more than one vessel is monitored) the scanning relay
changes state to supply the transmit pulse to the other transducer after the Scan delay
(2.1.14.) (Page 167).
Scan Delay is automatically set by Response rate (2.3.4.) (Page 174). When high speed
scanning is required (sometimes the case for equipment position monitoring), the Scan
Delay may be reduced. Reduce the Scan Delay only as required, otherwise premature
scanning relay fatigue could occur.
When two transducers are connected and configured in a dual-point unit, the device will scan
each in turn via the scanner relay. When a single-point device is programmed for differential
or average level Operation (Sensor mode (2.1.3.) (Page 163) = Dual-Point Difference or
Dual-Point Average), two transducers of the same type must be used.
A.9 Volume calculation
The device provides a variety of volume calculation features such as:
● Vessel shape (2.7.2.) (Page 186)
● Maximum volume (2.7.3.) (Page 188)
● Dimension A (2.7.4.) (Page 188)
● Dimension L (2.7.5.) (Page 189)
If the vessel does not match any of the eight preset vessel shape calculations, a universal
volume calculation may be used. Use the level/volume graph or chart provided by the vessel
fabricator (or create one based on the vessel dimensions). Based on the graph, choose the
universal volume calculation and select the level vs. volume breakpoints to be entered
(maximum of 32). Generally, the more breakpoints entered, the greater the accuracy.
Vessel shape
1)
set to Universal Linear
This volume calculation creates a piece-wise linear approximation of the level/volume curve.
This option provides best results if the curve has sharp angles joining relatively linear
sections.
Enter a Level Breakpoint at each point where the level/volume curve bends sharply
(minimum of two). For combination curves (mostly linear but include one or more arcs), enter
numerous breakpoints along the arc, for best volume calculation accuracy.