Yokogawa EJA530A - Manual (Page 44)

IM 01C21F01-01E 8-13
8. BRAIN TERMINAL BT200 OPERATION
Note that changing the higher range value does not
cause the lower range value to change but does
change the span.
• Example 2: When the higher range value is to
be changed to 10 kPa with the
present setting of 0 to 30 kPa, take
the following action with an input
pressure of 10 kPa applied.
FEED NO OK
SET
H11:AUTO HRV
10.000 kPa
DATA DIAG PRNT ESC
PARAM
H10:AUTO LRV
0 kPa
H11:AUTO HRV
10.000 kPa
H60:SELF CHECK
GOOD
ESC
SET
H11:AUTO HRV
30 kPa
+ 30
The lower range value is not
changed, so the span changes.
Parameter C22 is changed at the
same time.
Press the key twice.
The higher range value is changed
to 10 kPa.
Press the (OK) key.
F0827.EPS
(12) Zero Point Adjustment
(J10: ZERO ADJ, J11: ZERO DEV,
J20: EXT ZERO ADJ)
The DPharp supports several adjustment methods.
Select the method best suited for the conditions of
your application.
Note that output signal can be checked by displaying
parameter A10:OUTPUT (%) on the BT200.
Adjustment Method Description
Using the BT200 Set the present input to 0%.
Using the external
zero-adjustment
screw
᭤ P.8-14
Adjust zero point using the zero-
adjustment screw on the transmitter.
This permits zero adjustment without
using the BT200. Accurately adjust
the output current to 4 mA DC or
other target output value using an
ammeter that accuratly reads output
currents.
Adjust output to the reference value
obtained using other means.
Adjust for 0% output at input level of
0%.
If the input level cannot easily be
made 0% (because of tank level,
etc.), adjust output to the reference
value obtained using other means,
such as a sight glass.
T0809.EPS
(a) Follow the procedure below when setting the
present output to 0% (4 mA).
FEED NO OK
SET
J10:ZERO ADJ
0.0 %
CLR ESC
SET
J10:ZERO ADJ
0.0 %
+ 000.0 Press the key twice.
Zero adjustment is completed.
Press the (OK) key.
F0828.EPS
Output is 0.5%.
A10:OUTPUT (%)
0.5 %
Output is 0%.
A10:OUTPUT (%)
0.0 %
(b) In tank level measurement, if the actual level
cannot be brought to zero for zero adjustment,
then the output can be adjusted to correspond to
the actual level obtained using another measuring
instrument such as a glass gauge.
[Example]
Measurement range: 50 to 250 kPa, Actual value:
130 kPa.
Actual value
Actual
value(%)
x 100
130–50
250–50
= x 100=40.0%
–Measurement range lower range value
Measurement range higher range value
–Measurement range lower range value
=
(b)-1 Follow the procedure below to use J10: ZERO
ADJ.
CLR ESC
SET
J10:ZERO ADJ
0.0 %
+ 040.0 Enter the present actual level, 40%.
Press the key twice.
The output is changed to 40%.
F0829.EPS
Present output is 41.0%.
A10:OUTPUT (%)
41.0 %
A10:OUTPUT (%)
40.0 %