Yokogawa EJA110E - Manual (Page 38)

<7. Operation>
7-5
IM 01C25B01-01E
7.5.2 Venting Gas
1) Gradually open the vent screw to vent gas from
the transmitter pressure-detector section. (See
figure 7.6.)
2) When the transmitter is completely vented,
close the vent screw.
3) Tighten the vent screw to a torque of 10 N·m.
When you loosen the vent screw, the gas
escpes in the direction of the arrow.
F0707.ai
Vent screw
Vent screw
Figure 7.6 Venting the Transmitter
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 the transmitter. (Note 1)
4) Turn the external zero-adjustment screw in the
desired direction. The integral indicator displays
the output signal in %. (Note 2)
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.
(Note 1)
8) Turn the external zero-adjustment screw in the
desired direction. The integral indicator displays
the output signal in %. (Note 2)
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.