Operation; Preparation For Starting Operation - YOKOGAWA DpharpEJX vigilantplant EJX110 User Manual

7.

OPERATION

7.1 Preparation for Starting
Operation
This section describes the operation procedure for the
EJX110A as shown in figure 7.1a (vertical impulse
piping type, high-pressure connection: right side) when
measuring the liquid flow rate, and EJX430A and
EJX310A as shown in figure 7.1b when measuring
pressure.
NOTE
Check that the process pressure tap valves,
drain valves, and 3-valve manifold stop valves
on both the low pressure and high pressure
sides are closed, and that the 3-valve manifold
equalizing valve is opened.
(a) Follow the procedures below to introduce process
pressure into the impulse piping and transmitter.
Differential Pressure Transmitters
1) Open the low pressure and high pressure tap valves
to fill the impulse piping with process liquid.
2) Slowly open the high pressure stop valve to fill the
transmitter pressure-detector section with process
liquid.
3) Close the high pressure stop valve.
4) Gradually open the low pressure stop valve and
completely fill the transmitter pressure-detector
section with process liquid.
5) Close the low pressure stop valve.
6) Gradually open the high pressure stop valve. At this
time, equal pressure is applied to the low and high
pressure sides of the transmitter.
7) Check that there are no liquid leaks in the impulse
piping, 3-valve manifold, transmitter, or other
components.
Gauge/Absolute Pressure Transmitters
1) Open the tap valve (main valve) to fill the impulse
piping with process fluid.
2) Gradually open the stop valve to introduce process
fluid into the transmitter pressure-detector section.
3) Confirm that there is no pressure leak in the
impulse piping, transmitter, or other components.
Venting Gas from the Transmitter Pressure-
detector Section
• Since the piping in the example of figure 7.1 is
constructed to be self-venting, no venting operation is
required. If it is not possible to make the piping self-
venting, refer to subsection 7.5 for instructions.
Leave the equalizing valve open even after venting
gas.
(b) Turn ON power and connect the communicator.
Open the terminal box cover, and connect the
communicator to the SUPPLY + and – terminals.
(c) Using the communicator, confirm that the transmit-
ter is operating properly. Check parameter values or
change the setpoints as necessary.
See IM 01C25T03-01E (BRAIN communication) or
IM 01C25T01-01E (HART communication) for
communicator operation.
If the transmitter is equipped with an integral
indicator, its indication can be used to confirm that
the transmitter is operating properly.
Tap valve
(low pressure)
Stop valve
(low pressure)
Equalizing valve
Stop valve
(high pressure)
Figure 7.1a Liquid Flow Measurement
7-1
7. OPERATION
Orifice
Tap valve
(high pressure)
3-valve manifold
Drain valve
(high pressure)
F0701a.EPS
IM 01C25B01-01E