Yokogawa EJX440A - Manual (Page 15)

IM 01C25T03-01E 3-7
3. OPERATION
b. Setting Calibration Range Lower
Range Value and Upper Range Value
(C21: PRES LRV, C22: PRES URV)
These range values are set as specified in the order
before the instrument is shipped. Follow the procedure
below to change the range.
• The measurement span is determined by the upper
and lower range limit values. In this instrument,
changing the lower range value also automatically
changes the upper range value, keeping the span
constant.
• Example 1: With present settings of 0 to 30 kPa,
set the lower range value to 0.5 kPa.
Span = Upper range value – Lower range value
FEED NO OK
SET
C21:PRES LRV
0.5 kPa
DATA DIAG PRNT ESC
PARAM
C20:PRES UNIT
kPa
C21:PRES LRV
0.5 kPa
C22:PRES URV
30.5 kPa
DEL CLR ESC
SET
C21:PRES LRV
0 kPa
+ 0.5
The upper range value is changed
while the span remains constant.
Set 0.5.
Press the key twice to
enter the setting.
Press the (OK) key.
F0311.EPS
• Entering the range values as LRV>URV reverses the
direction of the output signal of 4-20 mA to 20-4 mA
corresponding to the calibration range of 0 to 100%.
• Calibration range can be specified with range value
specifications up to 5 digits (excluding any decimal
point) for lower or upper range limits within the
range of –32000 to 32000.
• Note, however, that changing the upper range value
does not cause the lower range value to change.
Thus, changing the upper range value also changes
the span.
• Example 2: With present settings of 0 to 30 kPa,
set the upper range value to 10 kPa.
FEED NO OK
SET
C22:PRES URV
10 kPa
DATA DIAG PRNT ESC
PARAM
C20:PRES UNIT
kPa
C21:PRES LRV
0 kPa
C22:PRES URV
10 kPa
DEL CLR ESC
SET
C22:PRES URV
30 kPa
+ 10
The lower range value is not
changed, so the span changes.
Set 10.
Press the key twice
to enter the setting.
F0312.EPS
Press the (OK) key.
(3) Damping Time Constant Setup
(C30: AMP DAMPING)
When the instrument is shipped, the damping time
constant is set at 2.00 seconds unless otherwise
specified in the order. Follow the procedure below to
change the damping time constant.
Note that setting the quick response parameter (D50:
QUICK RESP) ON enables you to set the damping
time constant between 0.00 to 0.49 second.
• Example: Change from 2.00 sec to 4.00 sec.
ESC CLR
SET
C30:AMP DAMPING
4.00 sec
FEED NO OK
SET
C30:AMP DAMPING
2.00 sec
+ 004.00 Enter 4.
Press the key twice to
enter the setting.
F0313.EPS
Press the (OK) key.
Note 1: The damping time constant set here is the time constant for
the amplifier assembly. The damping time constant for the
entire transmitter is the sum of the values for the amplifier
assembly and for the capsule assembly.
Note 2: When the damping time constant is set to less than 0.5
second, communication may occasionally be unavailble
during the operation, especially while output changes
dynamically.