Emerson Rosemount 3051 Reference Manual page 85

Reference Manual
00809-0100-4001, Rev JA
1.
2.
3.
4.
5.
Sample calculation for a standard 3051C
Step 1: Determine the performance required for your application.
Required Performance:
Step 2: Determine the operating conditions.
Transmitter:
Calibrated Span:
Ambient Temperature Change:
Line Pressure:
Step 3: Calculate total probable error (TPE).
TPE =
Where:
Reference Accuracy =
Ambient Temperature Effect =
Span Static Pressure Effect
(1)Zero static pressure effect removed by zero trimming at line pressure.
Step 4: Calculate the stability per month.
Stability
Step 5: Calculate calibration frequency.
Sample calculation for 3051C with P8 option
(0.04% accuracy & 5-year stability)
Step 1: Determine the performance required for your application.
Required Performance:
Operation and maintenance
Determine the performance required for your application.
Determine the operating conditions.
Calculate the Total Probable Error (TPE).
Calculate the stability per month.
Calculate the calibration frequency.
2
  
ReferenceAccuracy + TemperatureEffect


0.0125

----------------------------------------- -

(1)
=
0.1% reading per 1000 psi (69 bar)
URL 
(0.125 ¥

-------------------------------------- - % of span for 5 years
=
Span

Req. Performance TPE
Cal. Freq. = ---------------------------------------------------------------------- -
Stability per Month
Section 4: Operation and Maintenance
0.30% of span
3051CD, Range 2 [URL=250 inH
150 inH O (374 mbar)
2
± 50 °F (28 °C)
500 psig (34,5 bar)
2 2
  
+ StaticPressureEffect
± 0.065% of span

 % per 50 °F
¥ URL
+ 0.0625

Span

= 0.05% of span at maximum span

= 0.0035% of span per month
  
– 0.30% 0.117% –
= ------------------------------------------------ -
0.0035%
0.30% of span
November 2012
O(623 mbar)]
2
= 0.117% of span

= 0.0833% of span
 months
= 52
75