Emerson Rosemount 1152 Alphaline, Справочное руководство

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Reference Manual
00809-0100-4235, Rev BA
April 2007
Rosemount 1152
3-4
Figure 3-2. Adjustable Damping,
D Output.
NOTE
If you remove either cover during the above procedures, replace the O-ring
and torque the cover per the instructions provided in Section 5: Maintenance
and Troubleshooting. Spare cover O-rings are supplied with each transmitter.
CALIBRATION (E, N,
AND L OUTPUT)
Rosemount 1152DP, HP, GP, and AP Transmitters are factory calibrated to the
range shown on the nameplate. This range may be changed within the limits
of the transmitter. Zero may also be adjusted to elevate (for all models except
Rosemount 1152AP) or suppress (for all models). The span and zero
adjustments are external and located under the nameplate.
Span Adjustment
(E, N, and L Output)
The span on any Rosemount 1152 Transmitter is continuously adjustable to
allow calibration anywhere between maximum span and
1 /
6
of maximum span.
For example, the span on a Range Code 4 transmitter can be continuously
adjusted between 0–25 inH
2
O and 0–150 inH
2
O.
Zero Adjustment
(E, N, and L Output)
The zero on a Rosemount 1152 Transmitter with the E, N, or L output can be
adjusted for up to 500 percent of span suppression or 600 percent of span
elevation (see Figure 3-3 on page 3-5 for E or N output).
The zero may be elevated or suppressed to these extremes with the limitation
that no applied pressure within the calibrated range exceeds the full-range
pressure limit. For example, a Range Code 4 transmitter cannot be calibrated
for 150 to 200 inH
2
O (only 300 percent zero suppression) because the 200
inH
2
O exceeds the 150 inH
2
O full-range pressure limit of Range Code 4.
The transmitter may be calibrated to cross zero (e.g., –75 to 75 inH
2
O) but
this may result in a slight loss of linearity.
Four-Position
Rotary Switch
Linearity
Adjustment
1152-0395A