DayTronic 3500 Series, Инструкция по эксплуатации

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b. Once again, press
This will return you temporarily to a display of the "live" analog input.
c. Apply an accurately known value of input loading to the source transducer—a
value less than 50% of the nominal full-scale range. If it is possible to set this
"zero point" load equal to the minimum value of the transducer's rated operat-
ing range, you should do so. For a displacement sensor, for example, such a
load value is obtained when the sensor is in its "NULL" position.
d. Now press ANY KEY EXCEPT CAL OR SETUP . This will freeze the displayed
data value, which should be the value of input loading at your first ("zero") cali-
bration point.
NOTE: THOUGH THE DISPLAYED INPUT VALUE IS FROZEN, THE INPUT
ITSELF IS NOT. "ZERO" CALIBRATION WILL BE BASED ON WHATEVER
ACTUAL INPUT EXISTS WHEN THAT CALIBRATION POINT IS ENTERED.
e. Using the NUMERIC BUTTONS as explained in Section 1.e, change the dis-
played value to the desired measurement reading for the known input,
expressed in appropriate engineering units and with appropriate polarity.
Note that the button labelled
is now lit. This button enables you to change the DECIMAL-POINT LOCATION
of the displayed number during the "FORCE" procedure, below. Pressing
DEC will move the decimal point one digit to the left—or, when the decimal
point is at the leftmost position, to remove it (thus returning the number to an
integral value). Remember, too, that your offset entry cannot exceed the
inherent number count of ±32700.
f. Press ENTER to establish your first calibration point. The display will return to
"OFSET." Now press CAL . The unit will display the word "FORCE":
g. Press ENTER . If your unit is a Model 3510, 3530, 3540, or 3560 , this will
return you temporarily to a display of the "live" analog input. Proceed directly
to Step h, below.
If, however, your unit is a Strain Gage Conditioner (Model 3570 or 3578) , it
will display the mnemonic for "SHUNT CALIBRATION—POSITIVE":
You now have the opportunity to connect the internal shunt resistor for a posi-
tive up-scale reading. For the complete SHUNT CALIBRATION procedure, go
directly to the following section (3.c.3). If you are performing "actual" two-
point calibration, just press the
CAL button here. The unit will display the
mnemonic for "SHUNT CALIBRATION—NEGATIVE":
4.9
S
ETUP
: I
NSTRUMENT
C
ALIBRATION
4
4.c C
ALIBRATING
T
HROUGH THE
F
RONT
P
ANEL
ENTER
DEC