Yokogawa EJX930A - Manual (Page 57)

<7. In-Process Operation>
7-2
IM 01C25R03-01E
7.3 Simulation Function
There are two simulation functions in EJX
multivariable transmitter; one is the function
commonly offered in F OUNDATION Fieldbus products
to simulate input of each function block for loop
check, and the other is the flow simulation function
to simulate measured inputs for checking the result
of flow calculation.
The simulation function described in this section is
the former one. For flow simulation function, see
‘6.3.6 Simulation Function.’
The simulation function simulates the input of a
function block and lets it operate as if the data was
received from the transducer block. It is possible to
conduct testing for the downstream function blocks
or alarm processes.
A SIMULATE_ENABLE switch is mounted in the
amplifier. This is to prevent the accidental operation
of this function. When this is switched on, simulation
is enabled. (See Figure 7.2.) To initiate the same
action from a remote terminal, if REMOTE LOOP
TEST SWITCH is written to the SIM_ENABLE_
MSG parameter (index 1044) of the resource block,
the resulting action is the same as is taken when
the above switch is on. Note that this parameter
value is lost when the power is turned OFF. In
simulation enabled status, an alarm is generated
from the resource block, and other device alarms
will be masked; for this reason the simulation must
be disabled immediately after using this function.
The SIMULATE parameter of AI block consists of
the elements listed in Table 7.2 below.
Table 7.2 SIMULATE Parameter
Subindex Parameters Description
1 Simulate Status Sets the data status to
be simulated.
2 Simulate Value Sets the value of the
data to be simulated.
3 Transducer Status Displays the data status
from the transducer
block. It cannot be
changed.
4 Transducer Value Displays the data value
from the transducer
block.It cannot be
changed.
5 Simulate
En/Disable
Controls the simulation
function of this block.
1: Simulation disabled
(standard)
2: Simulation started
When Simulate En/Disable in Table 7.2 above is
set to 2, the applicable function block uses the
simulation value set in this parameter instead of
the data from the transducer block. This setting can
be used for propagation of the status to the trailing
blocks, generation of a process alarm, and as an
operation test for trailing blocks.
F0702.ai
Amplifier Assembly
1
2 O
N
"OFF" during operation
Not in use
SIMULATE_ENABLE
Figure 7.2 SIMULATE_ENABLE Switch Position