Yokogawa EJX430B - Manual (Page 35)

<7. Operation>
7-3
IM 01C27B01-01EN
(1) When you can obtain the Low Range Value
from the actual measured value of 0%
(0 kPa, atmospheric pressure);
■ Using the transmitter’s zero-adjustment
screw
Before adjusting zero point, make sure followings.
• The External zero trim parameter (External
Zero Trim) is “Trim on”. For details, refer to
section 8 “Setting Parameters”.
• Use a slotted screwdriver to turn the zero-
adjustment screw. Turn the screw clockwise
to increase the output or counterclockwise to
decrease the output.
The zero point adjustment can be made with
a resolution of 0.01% of the setting range. The
degree of zero adjustments varies with the screw
turning speed; turn the screw slowly to make a fine
adjustment, quickly to make a rough adjustment.
■ Using the Device Configuration Tool
Refer to subsection 8.3.14 “Zero Point Adjustment
and Span Adjustment”.
(2) When you cannot obtain the Low Range
Value from the actual measured value of
0%;
Adjust the transmitter output value matches to
the actual measured value obtained by precise
pressure measurement equipment.
[Example]
The measuring range of 50 to 250 kPa; the actual
measured value of 130 kPa.
130–50
250–50
Actual measured value= x100=40.0%
■ Using the transmitter’s zero-adjustment
screw
Turn the zero adjustment screw to match the output
signal to the actual measured value.
■ Using the Device Configuration Tool
Refer to subsection 8.3.14 ”Zero Point Adjustment
and Span Adjustment”.
7.3 Starting Operation
After completing the zero point adjustment, follow
the procedures below to start operation. Steps
1) and 2) are specific to the differential pressure
transmitters.
1) Close the equalizing valve.
2) Gradually open the low pressure stop valve.
This places the transmitter in an operational
condition.
3) After confirming the operating status, perform
the following.
IMPORTANT
• Close the terminal box cover and the
amplifier cover. Screw each cover in tightly
until it will not turn further.
• Tighten the zero-adjustment cover mounting
screw to secure the cover.
7.4 Connecting to the Field
Wireless Network
■ Preparation work prior to connecting to a
Field Wireless Network
This transmitter does not need to be connected
with a physical wire. Instead of physical wiring, it
is necessary to set the field wireless devices to
communicate with before installing the transmitter.
This procedure is called a provisioning.
This transmitter supports provisioning via infrared
communication using a provisioning device and
can be securely connected to a network. If the
provisioning information is not set, the transmitter
cannot be connected to the field wireless network.
Provisioning:
Provisioning is work to set the security and
network information to enable the transmitter
to be connected to the field wireless network.
This transmitter supports a provisioning method
using infrared communication.
For details on provisioning using a provisioning
device, and procedure for connecting the
transmitter to the Field Wireless Network, refer
to the User’s Manual, FieldMate Versatile Device
Management Wizard (IM 01R01A01-01E),
YFGW710 Field Wireless Integrated Gateway (IM
01W01F01-01EN) and YFGW410 Field Wireless
Management Station (IM 01W02D01-01EN).