DayTronic 3500 Series, Instruction Manual

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NUMERIC BUTTONS to change it, if desired. Press ENTER to return to the
"SEG 0" display. Now you can add more points, if desired, or quit.
12. After you have defined the last segment of your curve, press SETUP to return
to the "Setup" display.
4.c.4.c B
Y
“FORCE”
NOTE: When you choose this linearization method, you will have to be able to
continuously vary the magnitude of the physical input, or "load," on the source
transducer, and to know the resulting output accurately in the desired engineer-
ing units.
1. Once you have pressed CAL after the display of "TABLE," the unit will display
the word "FORCE":
2. Press ENTER . The unit will display the word "SET" and a number from 0
through 15—for example:
If the linearization table has been reset or if you are linearizing your unit for
the first time, the displayed "SET" number will be "0," and you should proceed
to Step 3, below.
If, however, the existing table has NOT been reset, the displayed number will
be that of the line segment within whose input range the instrument's present
"live" input lies. If in Fig. 21, for example, the present input value (i) lies
between the values f
4
and f
5
, "SET 5" will be displayed, since this input range
corresponds to the endpoints of Segment No. 5. The thing to remember is
that, with linearization "by force," the displayed "SET" number is "live," and will
change as the instrument's "live" input changes (this is in fact the only way to
move from segment to segment, since the "SET" display digits are not
NUMERIC BUTTONS). Also note that if the present "live" input is less than the
existing "zero" point "z," the display will read "SET 0." To "reforce" an existing
line segment, see the procedure given in Step 11, below.
3. Press ENTER . This will return you temporarily to a display of the "live" analog
input.
4. Apply an accurately known MINIMUM value of input loading to the source
transducer (corresponding to the "zero" point "z" of the linearization curve).
5. Now press ANY KEY EXCEPT CAL OR SETUP . This will freeze the displayed
data value. NOTE: THOUGH THE DISPLAYED INPUT VALUE IS FROZEN, THE
INPUT ITSELF IS NOT. LINEARIZATION WILL BE BASED ON WHATEVER
ACTUAL INPUT EXISTS WHEN THAT POINT IS ENTERED.
6. Using the NUMERIC BUTTONS as explained in Section 1.e, change the dis-
played value to the desired measurement reading for the known input, in the
desired engineering units. As in Section 4.c.2, above, you can use the
DEC
4.15
S
ETUP
: I
NSTRUMENT
C
ALIBRATION
4
4.c C
ALIBRATING
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HROUGH THE
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RONT
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ANEL