Yokogawa EJX440A - Manual (Page 22)

<3. Operation>
3-12
IM 01C25T01-01E
The low cut point has hysteresis so that the output
around the point is behaved as below figure.
<Example>
Output mode: Linear
Low cut mode: Zero
Low cut: 20.00%
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Setting range: 0 to 20%
2% 2%
4mA
Output Low cut point
Input
Hysteresis
fixed at 10%
of the cut point
7.2mA
(20%)
3.4.7 Impulse Line Connection Orientation
Setup
This function reverses the impulse line orientation.
Follow the procedure below to make this change.
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(ENTER)
EJX:YOKOGAWA
H/L Swap
Normal
Normal
Reverse
HELP SEND ESC ENTER
Press SEND (F2) to send the
data to the transmitter, then
check to confirm that
disappears.
(SEND)
1. Device setup
3. Basic setup
9. H/L Swap
SEND
Call up the H/L Swap Display
Select Reverse, and press
ENTER (F4).
EJX:YOKOGAWA
Basic setup
5 Xfer fnctn Linear
6 Pres Damp 0.50 sec
7 Low cut 20.00 %
8 Low cut mode Zero
9 H/L Swap Reverse
HELP SEND HOME
Example: Assign the high pressure impulse line connection
to the L side of the transmitter.
1
2
3.5 Detailed Setup
3.5.1 Bi-directional Flow Measurement
(a) Bi-dir mode enables selection of 50% output at
an input of 0 mmH
2
O.
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(ENTER)
EJX:YOKOGAWA
Bi-dir mode
Off
off
on
HELP SEND ESC ENTER
1. Device setup
4. Detailed setup
2. Signal condition
9. Bi-dir mode
Example: If measurement range is 0 to 3000mmH
2
O
(LRV = 0 mmH
2
O, URV = 3000 mmH
2
O)
Press SEND (F2) to send the data
to the transmitter, then check to
confirm that disappears.
Note: The measurement range changes to −3000 to 0 to
3000 mmH
2
O, corresponding the output of 0% to
50% to 100%. Note that LRV and URV values are
not changed.
(SEND)
SEND
Call up the Bi-dir mode display
Select on, and press ENTER (F4).
EJX:YOKOGAWA
Signal condition
5 Pres Damp 0.50 sec
6 Low cut 20.00 %
7 Low cut mode Zero
8 H/L swap Reverse
9 Bi-dir mode On
HELP SEND HOME
1
2
(b) Combining Bi-dir mode with Xfer fnctn
provides a square root output computed
independently for 0% to 50% output and for
50% to 100% output.
20 mA (100% display)
4 mA (−100% display)
 Output mode “LINEAR”
LRV HRV
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20 mA (100% display)
Low Cut
4 mA (−100% display)
 Output mode “SQUARE ROOT”
LRV HRV