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Reference Manual
00809-0100-4001, Rev JA
Section 4: Operation and Maintenance
November 2012
Operation and maintenance
Zero effect
Example: Line pressure is 3000 psi (207 bar) for Ultra performance transmitter. Zero effect error
calculation:
± {0.05 + 0.1 x [3 kpsi - 2 kpsi]} = ± 0.15% of the upper range limit
Span effect
Refer to “Line Pressure Effect” on page 105.
4.5.6 Compensating for line pressure
Rosemount 3051 Range 4 and 5 pressure transmitters require a special calibration procedure
when used in differential pressure applications. The purpose of this procedure is to optimize
transmitter performance by reducing the effect of static line pressure in these applications. The
3051 differential pressure transmitters (Ranges 1, 2, and 3) do not require this procedure
because optimization occurs in the sensor.
Applying high static pressure to 3051 Range 4 and Range 5 pressure transmitters causes a
systematic shift in the output. This shift is linear with static pressure; correct it by performing
the Sensor Trim procedure on page 83.
The following specifications show the static pressure effect for 3051 Range 4 and Range 5
transmitters used in differential pressure applications:
Zero Effect:
± 0.1% of the upper range limit per 1000 psi (69 bar) for line pressures from 0 to 2000 psi (0 to
138 bar)
For line pressures above 2000 psi (138 bar), the zero effect error is ± 0.2% of the upper range
limit plus an additional ± 0.2% of upper range limit error for each 1000 psi (69 bar) of line
pressure above 2000 psi (138 bar).
Example: Line pressure is 3000 psi (3 kpsi). Zero effect error calculation:
± {0.2 + 0.2 x [3 kpsi - 2 kpsi]} = ± 0.4% of the upper range limit
Span Effect:
Correctable to ±0.2% of reading per 1000 psi (69 bar) for line pressures from 0 to 3626 psi (0 to
250 bar)
The systematic span shift caused by the application of static line pressure is -1.00% of reading
per 1000 psi (69 bar) for Range 4 transmitters, and -1.25% of reading per 1000 psi (69 bar) for
Range 5 transmitters.
Use the following example to compute corrected input values.
± 0.1% of the upper range limit plus an additional ± 0.1% of upper range
limit error for each 1000 psi (69 bar) of line pressure above 2000 psi (138
bar).
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