Endress+Hauser Deltapilot S DB50, Техническая информация

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Deltapilot S
Hauser 13
Explanation of terms • A turn down of TD = 10:1 is possible with the following electronic inserts:
– 4 to 20 mA HART – FEB22(P)
– PROFIBUS PA – FEB24(P)
– FOUNDATION Fieldbus – FEB26
Turn down is possible via the signal processing units for electronic inserts 0.2 to 1.2 mA analog – FEB11(P)
and PFM – FEB17(P).
→
See "Function and system design" chapter, "Measuring device" section.
Explanation of terms: turn down (TD),
set span and span based on zero point
Case 1:
•
⏐
Lower range value (LRV)
⏐ ≤ ⏐
Upper range value
(URV)
⏐
Example:
• Lower range value (LRV) = 0 mbar
• Upper range value (URV) = 40 mbar
• Nominal value (URL) = 400 mbar
Turn down:
• Nominal value /
⏐
upper range value (URV)
⏐
=
400 mbar/40 mbar
TD = 10:1
Set span :
• Upper range value (URV) – lower range value (LRV) =
40 mbar – 0 mbar
Set span = 40 mbar
This span is based on the zero point.
P01-DBxxxxxx-05-xx-xx-xx-001
Example: 400 mbar measuring cell
Case 2:
•
⏐
Lower range value (LRV)
⏐ ≥ ⏐
Upper range value
(URV)
⏐
Example:
• Lower range value (LRV) = –200 mbar
• Upper range value (URV) = 0 bar
• Nominal value (URL) = 400 mbar
Turn down:
• Nominal value /
⏐
lower range value (LRV)
⏐
= 400 mbar/200 mbar
TD 2:1
Set span:
• Upper range value (URV) – lower range value (LRV) =
0 mbar – (–200 mbar)
Set span = 200 mbar
This span is based on the zero point.
P01-DBxxxxxx-05-xx-xx-xx-002
Example: 400 mbar measuring cell
1 Set span
2 Span based on zero point
3 Nominal value
i
upper range limit (URL)
4 Nominal measuring range
5 Sensor measuring range
LRL Lower range limit
URL Upper range limit
LRV Lower range value
URV Upper range value
–400 mbar 0 +400 mbar 40
LRL LRV URL URV
➁ ➀
=
➂
➃
➄
–400 mbar
+400 mbar
LRV
URL URV
➂
0
LRL
–200 mbar
➁ ➀
=
➃
➄