Specifications and Reference Data
March 2016
Reference Manual
00809-0100-4772, Rev FA
112
Specifications and Reference Data
Table A-4. Determining the PPL
Minimum downstream pressure (liquids)
Flow metering conditions that would allow cavitation, the
release of vapor from a liquid, should be avoided. This flow
condition can be avoided by remaining within the proper
flow range of the meter and by following appropriate
system design.
For some liquid applications, incorporation of a back
pressure valve should be considered. To prevent cavitation,
the minimum downstream pressure should be:
A.3 Performance specifications
The following performance specifications are for all
Rosemount models except where noted. Digital
performance specifications applicable to Fieldbus output.
Flow accuracy
Includes linearity, hysteresis, and repeatability.
Liquids—for Reynolds Numbers over 20000
Gas and steam— for Reynolds Numbers over 15,000
Note
As the meter Reynolds Numbers decreases below the
stated limit to 10,000 the accuracy error band will
increase linearly to +/-2.0%. For Reynolds Numbers
down to 5,000 the accuracy error band will increase
linearly from +/-2.0% to +/-6.0%.
Process temperature accuracy
2.2° F (1.2° C) or 0.4% of reading (in °C), whichever is
greater.
Mass flow accuracy for temperature compensated mass
flow
2.0% of rate (Typical)
Repeatability
± 0.1% of actual flow rate
Stability
±0.1% of rate over one year
Process temperature effect
Automatic K-factor correction with user-entered process
temperature.
Ta bl e A -5 indicates the percent change in K-factor per 100
°F (55.5 °C) in process temperature from reference
temperature of 77 °F (25 °C).
Meter
style
English units SI units
A
Liquid
A
Gas
A
Liquid
A
Gas
8800DF/W 3.4 ×10
-5
1.9 × 10
-3
0.425 118
8800DR 3.91×10
-5
2.19 ×
10
-3
0.489 136
8800DD
(1)
1. For all 6-in. thru 12-in. line sizes A is the same for Rosemount
8800DD and 8800DF
6.12 ×10
-5
3.42 ×
10
-3
0.765 212
P =
2.9∗ΔP + 1.3∗p
v
or P = 2.9∗ΔP + p
v
+ 0.5 psia (3.45
kPa) (use the smaller of the two results)
P =
Line pressure five pipe diameters downstream of
the meter (psia or kPa abs)
ΔP = Pressure loss across the meter (psi or kPa)
p
v
=
Liquid vapor pressure at operating conditions (psia
or kPa abs)
±0.65% of rate
Note: The accuracy for the Rosemount 8800DR, line sizes
6 to 12 inch (150 to 300mm), is ±1.0% of rate.
±1.0% of rate
Note: The accuracy for the Rosemount 8800DR, line
sizes 6 to 12 inch (150 to 300mm), is ±1.35% of rate.
Accuracy limitations for gas and steam:
- for
1
/2- and 1-in. (DN 15 and DN 25): max velocity of
220 ft/s (67.06 m/s)
- for Dual-style meters (
1
/2-in. to 4 in.): max velocity of
100 ft/s (30.5 m/s)
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