Setting The Range Using The Range-Setting Switch - YOKOGAWA DpharpEJX vigilantplant EJX110 User Manual

7.6 Setting the Range Using the
Range-setting Switch
WARNING
The range setting switch must not be used in the
hazardous area.
When it is necessary to use the switch, operate
it in a non-hazardous location.
When pressure is applied to the transmitter, the low-
and high-limit values for the measurement range (LRV
and URV) can be changed (re-ranged) using the range-
setting switch (push-button) located on the optional
integral indicator plate and the external zero adjustment
screw. This procedure does not require use of the
communicator. However, changes in the scale range
and engineering unit display settings for the integral
indicator require use of the communicator.
Follow the procedure below to change the LRV and
URV settings.
[Example]
Rerange LRV to 0 and URV to 3 MPa.
1) Connect the transmitter and apparatus as shown in
Figure 8.1 and warm it up for at least five minutes.
2) Press the range-setting push-button.
The integral indicator then displays "LRV.SET."
3) Apply a pressure of 0 kPa (atmospheric pressure) to
(Note 1)
the transmitter.
4) Turn the external zero-adjustment screw in the
desired direction. The integral indicator displays the
(Note 2)
output signal in %.
5) Adjust the output signal to 0% (1 V DC) by rotating
the external zero-adjustment screw. Doing so
completes the LRV setting.
6) Press the range-setting push-button. The integral
indicator then displays "URV.SET."
7) Apply a pressure of 3 MPa to the transmitter.
8) Turn the external zero-adjustment screw in the
desired direction. The integral indicator displays the
(Note 2)
output signal in %.
9) Adjust the output signal to 100% (5 V DC) by
rotating the external zero-adjustment screw. Doing
so completes the URV setting.
10) Press the range-setting push-button. The transmitter
then switches back to the normal operation mode
with the measurement range of 0 to 3 MPa.
Note 1: Wait until the pressure inside the pressure-detector section
has stabilized before proceeding to the next step.
Note 2: If the pressure applied to the transmitter exceeds the previous
LRV (or URV), the integral indicator may display error
number "AL.30" (In this case, the output signal percent and
"AL.30" are displayed alternately every two seconds).
Although "AL.30" is displayed, you may proceed to the next
step. However, should any other error number be displayed,
take the appropriate measure in reference to , "Errors and
Countermeasures" in each communication manual.
IMPORTANT
• Do not turn off the power to the transmitter
immediately after completion of the change in
the LRV and/or URV setting(s). Note that
powering off within thirty seconds after setting
will cause a return to the previous settings.
• Changing LRV automatically changes URV to
the following value.
URV = previous URV + (new LRV – previous LRV)
• If the range-setting push-button and external
zero-adjustment screw are not touched during a
range-change operation, the transmitter auto-
matically switches back to the normal operation
mode.
Integral indicator
Figure 7.7
(Note 1)
7-5
Note : Use a thin bar which
Range-setting switch
(Push-button)
Range-setting Switch
7. OPERATION
has a blunt tip, e.g.,
a hexagonal wrench,
to press the range-
setting push-button
F0707.EPS
IM 01C25B01-01E