Rosemount 890, Инструкция по эксплуатации

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I
NITIAL
S
TARTUP AND
C
ALIBRATION
Rosemount Analytical 748460-A January 2000
3-22
Toggle and keys to select YES or NO.
Toggle and keys to select between 0 to 20
mA and 4 to 20 mA.
and will return analyzer to RUN mode
SHIFT ENTER
ENTER
SHIFT
CURRENT: X 20mA
ZR/SPN SUPR: YES
XX TO XXX FS
Note: Current Output is factory set at 4 to 20 mA. If an adjustment is needed, Zero and Span pots are located on the
Power Supply Board.
3.15 CURRENT OUTPUT
The Model 890 Analyzer has a standard 0 to 20 or 4 to 20 mA current output with zero
span suppression. This function can represent any suppressed range with at least a
25% span. For example. a valid range could be 0% to 25%, 28% to 61% or 33% to
100%. When the Zero Span Suppression is off (NO), the analyzer defaults to the 0%
to 100% range. Refer to Figure 3-14.
F
IGURE
3-14. C
URRENT
O
UTPUT
M
ODE
3.16 AUTO ZERO/SPAN
Refer to Figure 3-15. The Auto Zero/Span allows automatic, unattended calibration at
set intervals. The option has six contact closures, four of which are field programmable
for frequency and duration of the calibration cycle (span 1, span 2, span 3 and zero).
Meanwhile, the other two contact closures indicate insufficient zero and span
adjustments and also drift limits for zero and span, if activated.
The auto zero/span [AUTO-CAL: ON] display allows the user to select ON or OFF to
turn the Auto Zero/Span “on” or “off”. Toggling from OFF to ON resets the timers for
the Auto Zero/Span. To reset the timers when the Auto Zero/Span is “on”, toggle from
ON to OFF to ON.
The sample and hold [SH: YES] display allows the user to select YES or NO to turn
the automatic sample and hold “on” or “off”. When the sample and hold feature is “on”,