Yokogawa digitalYEWFLO (DY-FF) - Manual (Page 41)

<7. IN-PROCESS OPERATION>
7-3
IM 01F06F00-01EN
7.2.2 Alarms and Events
Each digitalYEWFLO can report the following
alarms and events as alerts.
Analog Alerts (Generated when a process value
exceeds threshold)
By AI Block: Hi-Hi Alarm, Hi Alarm, Low
Alarm, Low-Low Alarm
Discrete Alerts (Generated when an abnormal
condition is detected)
By Resource Block: Block Alarm, Write Alarm
By
Transducer Block: Block Alarm
By AI Block: Block Alarm
By PID Block: Block Alarm
Update Alerts (Generated when a important
(restorable) parameter is updated)
By Resource Block: Update Event
By Transducer Block: Update Event
By AI Block:
Update Event
By PID Block: Update Event
An alert has the following structure:
Table 7.2 Alert Object
Subindex
Parameter
Name
Explanation
Analog
Alert
Discrete
Alert
Update
Alert
1 1 1 Block Index
Index of block from which
alert is generated
2 2 2 Alert Key
Alert Key copied from the
block
3 3 3
Standard
Type
Type of the alert
4 4 4 Mfr Type
Alert Name identifi ed by
manufacturer specifi c DD
5 5 5
Message
Type Reason of alert
notifi cation
6 6 6 Priority Priority of the alarm
7 7 7 Time Stamp
Time when this alert is fi rst
detected
8 8 Subcode
Enumerated cause of this
alert
9 9 Value Value of referenced data
10 10
Relative
Index Relative Index of
referenced data
8
Static
Revision Value of static revision
(ST_REV) of the block
11 11 9 Unit Index
Unit code of referenced
data
7.3 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 jumper switch is mounted
on the digitalYEWFLO’s amplifi er. This is to prevent
the accidental operation of this function. When
this is switched on, simulation is enabled. (Refer
to Figure 7.2.) To initiate the same action from a
remote terminal, if REMOTE LOOP TEST SWITCH
is written to SIM_ENABLE_MSG (index 1044)
parameter 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 7.3 below.
Table 7.3 SIMULATE Parameter
Sub-
index
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: Disabled (standard)
2: Active(simulation)
When Simulate En/Disable in Table 7.3 above is
set to “Active”, 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.
2
1
1
2
F0702.ai
Set to OFF during
normal operation.
Not used.
SIM. ENABLE Switch
Figure 7.2 SIMULATE_ENABLE Switch Position