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Level transmitter configuration can be very time consuming. Calculations required to determine proper range values for traditional transmitters can become complex due to the physical layout of an application.

With maintenance shops getting smaller, finding equipment that allows us to do more with fens becomes a priority. DPharp transmitters with advanced software functionality can eliminate these complex calculations.


Using typical smart or conventional products, all the following must be considered:

The specific gravity of the process SGP

Precise location of 0% and 100%

Specific Gravity of the capillary fill fluid
   (or sealing fluid used in impulse piping)

Exact orientation oi the transmitter to the vessel H2
Vertical distance between the process conn. H1

Depending on the application, the vessel may be open (referencing atmosphere) or closed (under a blanket pressure).

Elevation is typically used when the vessel is closed. To reference the blanket pressure, a low side remote seal may be used (or a wet leg). The capillary on remote seal creates a negative force on the transmitter equal to the vertical height times the specific gravity of the fill fluid.

Elevation = (H1 + H2) x SGFF

Suppression is a positive pressure created on the high-pressure side of the transmitter typically due to the transmitter being positioned below the 0% process connection. Suppression is present in both open arid closed vessels. Suppression is equal to the vertical distance between the 0% process connection and the transmitter times the Specific Gravity of the fill livid.

Suppression = H2 x SGFF

Span is the vertical distance between the process connections times the process medium's Specific Gravity.

Span = H1 x SGP

Figure 1: Closed Tank
Figure 1: Closed Tank

Now that you have the Elevation, Suppression, and Span, the calibration values can be calculated for the 0% (Empty) arid the 100% (Full).

Cal Value (0%) = Suppression - Elevation

Cal Value (100%) = (Suppression + Span) - Elevation

Example: (using figure 1)

SGP 0.9 H2 10 inches
SGFF 0.8 H1 20 inches

Cal Value 0%) = Suppression - Elevation
Cal Value (0%) = (H2 x SGFF) - (H1 + H2 x SGFF)
Cal Value (0%) = (10 x 0.8) - (20 + 10) x 0.8
Cal Value (0%) = 8 - 24
Cal Value 0%) = -16 inH2O

Cal Value (100%) = (Suppression + Span) - Elevation
Cal Value (100%) = ((H2 x SGFF) + (H1 x SGP)) - (H1 + H2) x SGFF
Cal Value (100%) = ((10 x 0.8) + (20 x 0.9)) - (20 + 10) x 0.8
Cal Value (100%) = (8 + 18) - 24
Cal Value (100%) = +2 inH2O

Therefore, Calibrated Range would be:

-16 inH2O  +2 inH2O
0% 100%
Empty Full








差壓(DP)定義為兩個壓力之間的差異。 差壓傳送器使用低壓側壓力的參考點,並與高壓側壓力進行比較。 儀器中的接口標記為高側和低側。


準確的液位讀數與工廠的安全、穩定跟獲利的運作息息相關。 液位傳送器測量壓差推斷容器中的液位。




絕對壓力傳送器比較相對於絕對壓力的壓力值。 絕對壓力始終是正值。


我們的壓力傳送器可選擇多種安裝方式,並均可提供準確且可重複的測量。 由於它基於大氣壓力,因此易於處理並可用於各種應用。


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