YOKOGAWA DpharpEJX vigilantplant EJX Series - External Switch Mode; CPU Failure Burnout Direction and Hardware Write Protect

IM 01C25T01-01E
3-22
3. OPERATION
3.5.11 External Switch Mode
Follow the procedure below to enable or inhibit zero
point adjustment by means of the zero-adjustment
screw on the transmitter.
This is set to Enabled when the instrument is shipped.
F0337.EPS
(ENTER)
EJX:
Ext SW
Enabled
Disabled
Enabled
HELP SEND ESC ENTER
Select Disabled and press ENTER
(F4).
1. Device setup
4. Detailed setup
5. Device information
1. Field device info
9. Ext SW
Example: Set the mode to inhibit zero adjustment by means
of the external zero-adjustment screw.
EJX:
Field device info
5 Model 1
6 Model 2
7 Model 3
8 Write Protect No
9 Ext SW Disabled
HELP SEND HOME ENTER
Press SEND (F2) to send the data
to the transmitter, then check to
confirm that disappears.
(SEND)
SEND
2
1
3.5.12 CPU Failure Burnout Direction and
Hardware Write Protect
There are two slide switches on the CPU assembly
board. One sets the burnout direction at CPU failure,
and the other sets a write protection function which
disables parameter changes through the use of a
handheld terminal or some other communication
method.
HIGH LOW
CPU assembly
Slide switch
Burnout direction switch
Write protection switch
Write Protection
Switch Position
Burnout Direction
Switch Position
BO H L
WR E D
H L
ED
H L
ED
HL
D
HL
EED
Hardware write protection switch (WR)
Burnout direction switch (BO)
Burnout Direction
Write Protection
YES
(Write disabled)
NO
(Write enabled)
F0340.EPS
The parameter of AO alm typ parameter displays the
status of 4-20 mA DC output if a CPU failure occurs.
In case of a failure, communication is disabled.
Standard specifications
The burnout direction switch is set to HIGH. If a
failure occurs, the transmitter outputs a 110% or higher
signal.
Option code /C1
The burnout direction switch is set to LOW. If a failure
occurs, a –5% or lower output is generated.
F0341.EPS
EJX:
Analog output
1 Loop test
2 D/A trim
3 Scaled D/A trim
4 Clear D/A trim
5 AO alm typ High
HELP SAVE HOME EXIT
1. Device setup
4. Detailed setup
3. Output condition
2. Analog output
5. AO alm typ
Example: Confirming the burnout direction at the CPU
failure.