Common pressure gauge temperature error calculation
Pressure gauge is the most commonly used industrial process instrumentation. In use, such as the use of ambient temperature gauge reference working conditions beyond the limited temperature range, ambient temperature gauge because of the impact of temperature errors produced. The temperature gauge natural common error calculation. A wide variety of pressure gauge, pressure gauge of the temperature error calculation is relatively complicated. This tool can not only gauge the temperature error calculation, can be calculated by the temperature of various gauge indication after the basic error limit. Also provides a popular and intuitive dial gauge the relative error of temperature minimum number of sub-grid!
• Step One: Select pressure gauge measuring the upper limit: MPa
• Step Two: Select Pressure Gauge Accuracy class: %
• Obtained: pressure gauge under reference conditions to allow the basic error limit ± MPa
• Step Three: Select the number of gauge plate compartments:
• Drawn: the smallest sub-dial cell value: MPa；Ambient temperature to allow the use of the basic error of the equivalent± smallest sub-grid
• Step four: Fill in the use of ambient temperature gauge:
• Step Five: Select the temperature gauge reference conditions:
• Drawn: the use of global environmental temperatures allow basic errors:± MPa
Note:
• For ordinary pressure gauge (both general pressure gauge) shows the use of ambient temperature should be in the range of -40 ~ 70 ℃ within.
• For the precision pressure gauge (also known as standard gauge) gives the use of environmental temperature should be in the range of 5 ~ 40 ℃ within.
• The temperature range beyond the limit should not use this tool to calculate, is a super scope.
• For ordinary pressure gauge (both general pressure gauge) when using the ambient temperature higher than 25 ℃, election 25 ℃; When ambient temperature is below 15 ℃, the election at 15 ℃.
• Precision pressure gauge for 0.4 (also known as the standard pressure gauge) when using the ambient temperature higher than 23 ℃ when the election 23 ℃; When the ambient temperature lower than 17 ℃ when the election at 17 ℃.
• For the 0.25 and 0.16, 0.1 precision pressure gauge (also known as standard pressure gauge) when using the ambient temperature higher than 22 ℃ when the election 22 ℃; when using the ambient temperature lower than 18 ℃ when the election at 18 ℃.

Pressure gauge temperature error calculation used to use to help
China's national standard stipulates that the use of ambient temperature gauge deviation from 20 ± 2 ℃ (0.25 Precision Pressure Gauge), 20 ± 3 ℃ (0.4 Precision Pressure Gauge) or 20 ± 5 ℃ (normal pressure gauge), the pressure gauge The indication error, (including zero)should not be greater than the limits prescribed by the following formula:
Δ = ±( δ + K Δt )
Formula: Δ ── Ambient temperature gauge deviation from 20 ± 2 ℃ (0.25 Precision Pressure Gauge), 20 ± 3 ℃ (0.4 Precision Pressure Gauge) or 20 ± 5 ℃ (normal pressure gauge) when the pressure indication error limit,%.
δ ── China's national standard value stipulated in the basic error of the pressure that the absolute limit,% .0.25 Precision Pressure Gauge 0.25% 0.4 0.4% precision pressure gauge, pressure gauge 1.6 General 1.6% 2.5 General Pressure Gauge 2.5%, 4.0 General pressure gauge was 4.0%.
Δt ── Deviate from the temperature values= | t2-t1 |,℃. Formula t2Chinese national standard gauge specified in the normal work environment within the temperature range of any value. Precision Pressure Gauge normal working temperature 5 ~ 40 ℃, the general gauge normal working temperature -40 ~ 70 ℃.Formula t1China's national standard for the election specified in the value of,When t2was higher than 22 ℃ (0.25 Precision Pressure Gauge) when 22 ℃,When t2was higher than 23 ℃ (0.4 Precision Pressure Gauge) when 23 ℃,When t2was higher than 25 ℃ (normal gauge) is 25 ℃,when t2lower than 18 ℃ (0.25 Precision Pressure Gauge) when 18 ℃, When t2lower than 17 ℃ (0.4 Precision Pressure Gauge) when 17 ℃, When t2lower than 15 ℃ (normal pressure gauge) when to 15 ℃.
K ── Affected by ambient temperature gauge factor, 0.04% / ℃ (does not apply to constant elastic material, elastic material constant K value calculated in accordance with the provisions of the relevant material standard.)

Use of environmental temperature gauge error calculation example:
Maximum value of a pressure gauge measuring 1MPa precision grade 0.4, dial grooves 200 points grid, the actual use of environmental temperature is 26 ℃.
Value δ = 0.4%    t2 = 23℃    t1 = 26℃    K = 0.04%/℃
Then Δt ── Deviate from the temperature values = | t2 - t1 |℃ = | 23℃ - 26℃ | = 3℃
Δ = ±( δ + K Δt ) = ±( 0.4% + 0.04%/℃ × 3℃ ) = ±( 0.4% + 0.12% ) = ±0.52%
Then, the pressure gauge at 26 ℃ ambient temperature to allow use of the basic error of ±( 1MPa × 0.52% ) = ±0.0052MPa
For the visual purposes, we use the gauge at 26 ℃ ambient temperature allowed under the fundamental error ±0.0052MPa Converted into the equivalent of the size of the smallest sub-grid:
The pressure gauge the value of the minimum sub-grid scale value = pressure gauge dial gauge groove ÷ total number of grid points = 1MPa ÷ 200 = 0.005MPa / sub-grid
The pressure gauge at 26 ℃ ambient temperature to allow use of the basic error of ± 0.0052MPa equivalent to the size of the smallest sub-grid = ± (ambient temperature gauge allows the use of basic error ÷ gauge the value of the smallest sub-grid) = ± ( 0.0052MPa ÷ 0.005MPa / sub-grid) = ± 1.04 sub-grid. not only to use the pressure gauge at 26 ℃ ambient temperature allowed under the basic error of indication ± 1.04 个 smallest compartments.

The sample temperature using the pressure gauge error calculation tools, operation sequence is:
• ① The upper limit of the pressure gauge measuring the drop-down list box, select 1MPa
• ② Accuracy class in the pressure gauge drop-down list box, select 0.4
• ③ Grid points in the pressure gauge dial the number of drop-down list box, select the 200 sub-grid
• ④ In the text box using the ambient temperature of 26
• ⑤ Reference temperature gauge conditions in the drop-down list box, select the 23 ℃. Later, the basic error in the indication limit the text box will show the temperature gauge in the reference work permit under the basic error of the results ± 0.004 MPa, in minimum value of sub-grid dial text box will show the minimum in the pressure gauge the value of sub-grid calculations 0.005 MPa, the fundamental error in allowing the equivalent of the text box will show a pressure gauge to deviate from the reference temperature conditions of the permit basic error is equivalent to gauge the size of the smallest sub-grid ± 1.04 个 smallest sub-cell, the fundamental error in allowing the text box showing the value of a gauge will appear to deviate from the reference temperature conditions, the basic error allowed, ± 0.0052 MPa .