Rosemount 1199 - Electronics Considerations; Maximum Span; The High Pressure Tap)

Model 1199 Diaphragm Seal Systems Manual
3-2
SI Units
Step 3
= 2,6 meters > h > 4,2 meters
NOTE
where:
(h) is the distance between the transmitter and the high pressure
tap. (h) is positive if the transmitter is mounted below the high
pressure tap and is negative if it is mounted above the tap. In this
case for a:
One Seal System Suppressed Zero (transmitter mounted below
the high pressure tap)
Do not mount the transmitter below the seal more than 100 inches
(2,6 meters) below the seal.
One Seal System Elevated Zero (transmitter mounted above the
high pressure tap)
Do not mount the transmitter more than 170 inches (4,2 meters)
above the seal.
Two Seal System Elevated Zero (independent of transmitter
location)
If it is necessary to measure an empty tank condition, the distance
between the seal taps should not exceed 170 inches (4,2 meters).
Electronics
Considerations
Zero elevation and suppression must be such that the lower range value
does not exceed the transmitter lower range limit (LRL), and the upper
range value is less than or equal to the transmitter upper range limit
(URL). The calibrated span must be greater than or equal to the minimum
span.
Maximum Span
For applications in which the transmitter is mounted above or below the
high pressure tap, be sure the calibrated span does not exceed the
transmitter minimum and maximum span limits.
URL ρ
f
gh ρ
p
gH⋅⋅+⋅⋅ LRL>>
620 mbar()h981,
1850
100
-------------
mbar
m
-----------------


15m,()981,
1000
100
-------------
mbar
m
-----------------


⋅⋅+⋅⋅ 620– mbar()>>
620 mbar()h981,185
mbar
m
-----------------


,15m,()981 10
mbar
m
-----------------


⋅,⋅+⋅⋅ 620 mbar()–>>
620 147–()mbar()
182
mbar
m
-----------------


------------------------------------------------------h
620– 147–()mbar()
182
mbar
m
-----------------


---------------------------------------------------------->>
1mbar
100
-----------------------
1kg m
3
⁄()1m s
2
⁄()1m()⋅⋅1N m
2
⁄==
NOTE
For the Model 3051 and 1151 Smart Transmitters, the maximum span
equals the difference between the upper and lower range limits.
For example, a Model 3051CD2 (Range Code 2) transmitter that has
an upper range limit of 250 inH
2
O (620 mbar) and a lower range limit
of –250 inH
2
O (- 620 mbar) has a maximum span capability of 500
inH
2
O (1,24 bar).
Step 4
Step 2
Step 1