YOKOGAWA YS1000 Series, User Manual

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1-4
IM 01B08D02-02EN
Alarm Detecting Function
This function can detect the high limit alarm (PH), low limit alarm (PL), high-high limit
alarm (HH), and low-low limit alarm (LL) with respect to process variables 1 and 2. Alarm
hysteresis can also be set for both process variables 1 and 2. The alarm detecting action
is shown in the figure below.
(If the high limit alarm and high-high limit alarm are set to the maximum values and
the low limit alarm and low-low limit alarm are set to the minimum values, no alarm is
detected.)
The following shows the relationship of alarm detection in parameters.
High limit alarm for PV1 (PH1) and high limit alarm for PV2 (PH2): Engineering units
equivalent to -6.3 to 106.3%
Low limit alarm for PV1 (PL1) and low limit alarm for PV2 (PL2): Engineering units
equivalent to -6.3 to 106.3%
High-high limit alarm for PV1 (HH1) and high-high limit alarm for PV2 (HH2): Engineering
units equivalent to -6.3 to 106.3%
Low-low limit alarm for PV1 (LL1) and low-low limit alarm for PV2 (LL2): Engineering
units equivalent to -6.3 to 106.3%
Alarm hysteresis 1 and alarm hysteresis 2: Engineering unit span equivalent to 0.1 to
20.0%
The following figure shows an example of actions of the high limit alarm for PV, high-high
limit alarm for PV, low limit alarm for PV, low-low limit alarm for PV, and alarm hysteresis.
PV
0604E.ai
High-high limit alarm output for PV
High limit alarm output for PV
High-high limit alarm setpoint for PV
High limit alarm setpoint for PV
Low limit alarm setpoint for PV
Low-low limit alarm setpoint for PV
Low limit alarm output for PV
Low-low limit alarm output for PV
For an example in the figure above, the contact type is such that the contact
opens if an event occurs (factory default).
Time
Alarm hysteresis (HYS)
Alarm hysteresis (HYS)
Alarm hysteresis (HYS)
Alarm hysteresis (HYS)
Closed Open
Closed Open
Closed Open
Closed
Open Closed
Setting Details
Parameter Name Setting Range
Display Transition and
Display Title
ASW1 to ASW6
Alarm output
connection
00000000 to 11111111
Tuning Display >
Engineering Display >
[ CONFIG3 ] (Configuration
Display 3)
ANOR1 to ANOR6
Alarm AND/
OR selection AND, OR
DO1D to DO6D
Alarm
contact type
OPN: When the alarm occurs,
the contact is opened.
CLS: When the alarm occurs,
the contact is closed.
1.3 Setting Alarm Function