Emerson Rosemount 1153 Series B, Справочное руководство

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Reference Manual
00809-0100-4302, Rev BA
January 2008
Rosemount 1153 Series B
3-6
Figure 3-4. Jumper Wire Placement for “R” and “P” Output with Turrets.
Linearity Adjustment
In addition to the span and zero adjustments, there is a linearity adjustment
located inside the transmitter on the amplifier board (see Figure 3-5 on
page 3-7). Linearity is factory calibrated for optimum performance over the
calibrated range of the instrument and is not normally adjusted in the field. If
you want to maximize linearity over some particular range, use the following
procedure:
1. Apply mid-range pressure and note the error between theoretical and
actual output signal.
2. Apply full-scale pressure. Multiply the error noted in step 1 by six and
by the rangedown factor:
3. Add the result to the full-scale output for negative errors, or subtract
the result from the full-scale output for positive errors, by adjusting the
linearity trimmer (see Figure 3-5). Example: At 4-to-1 rangedown the
midscale point is low by 0.05 mA. Therefore, adjust the “Linearity”
trimmer until full-scale output increases by (0.05 mA
⫻
6
⫻
4) = 1.2
mA.
4. Readjust zero and span.
NOTE
If you remove either cover during the above procedures, replace the O-ring
and torque the cover per the instructions given in
Section 5: Maintenance
and Troubleshooting . Spare cover O-rings are supplied with each
transmitter.
“R” OUTPUT AND “P” OUTPUT WITH TURRETS
Jumper Wire
Jumper Wire
DETAIL A
Moderate Elevation/Suppression
(no jumper Wire)
DETAIL B
(to Elevate Zero)
DETAIL C
(To Suppress Zero)
Rangedown Factor
Maximum Allowable Span
Calibrated Span
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