IDEC MICROSmart FC6A Series Ladder Programming Manual page 398

19: PID C I
ONTROL NSTRUCTION
10. Alarm Type
Select the type of alarm action from the following.
Type
No Alarm Action Do not output an alarm.
Turns ON the alarm output when process variable ≥
(set point + alarm value).
Turns OFF the alarm output when process variable ≤
(set point + alarm value - hysteresis).
When (set point + alarm value - hysteresis) < process
variable < (set point + alarm value), the alarm output
maintains the state of the previous scan.
Upper Limit Alarm
ON
OFF
- Alarm action point
Turns ON the alarm output when process variable ≤
(set point + alarm value).
Turns OFF the alarm output when process variable ≥
(set point + alarm value + hysteresis).
When (set point + alarm value) < process variable <
(set point + alarm value + hysteresis), the alarm
output maintains the state of the previous scan.
Lower Limit Alarm
- Alarm action point
Turns ON the alarm output when process variable ≥
(set point + alarm value).
Turns ON the alarm output when process variable ≤
(set point - alarm value).
Turns OFF the alarm output when (set point - alarm
value + hysteresis) ≤ process variable ≤ (set point +
alarm value - hysteresis).
When (set point + alarm value - hysteresis) < process
variable < (set point + alarm value), the alarm output
maintains the state of the previous scan.
When (set point - alarm value) < process variable <
Upper/Lower Limit
(set point - alarm value + hysteresis), the alarm
Alarm
output maintains the state of the previous scan.
ON
OFF
Alarm action point
19-8
Action
Alarm value
Hysteresis
Set point + Alarm action point
Alarm value
Hysteresis
ON
OFF
Set point + Alarm action point
Alarm value Alarm value
Hysteresis Hysteresis
Set point Alarm action point
FC6A S MICROS
ERIES MART
Set point: 200.0°C
Alarm value: 5.0°C
Hysteresis: 2.0°C
When process variable ≥ 205.0°C, the alarm output is turned ON.
When process variable ≤ 203.0°C, the alarm output is turned OFF.
Set point: 200.0°C
Alarm value: -5.0°C
Hysteresis: 2.0°C
When process variable ≥ 195.0°C, the alarm output is turned ON.
When process variable ≤ 193.0°C, the alarm output is turned OFF.
Set point: 200.0°C
Alarm value: 5.0°C
Hysteresis: 2.0°C
When process variable ≤ 205.0°C, the alarm output is turned ON.
When process variable ≥ 207.0°C, the alarm output is turned OFF.
Set point: 200.0°C
Alarm value: -5.0°C
Hysteresis: 2.0°C
When process variable ≤ 195.0°C, the alarm output is turned ON.
When process variable ≥ 197.0°C, the alarm output is turned OFF.
Set point: 200.0°C
Alarm value: 5.0°C
Hysteresis: 2.0°C
When process variable ≥ 205.0°C, the alarm output is turned ON.
When process variable ≤ 195.0°C, the alarm output is turned ON.
When 197.0°C ≤ process variable ≤ 203.0°C, the alarm output is turned OFF.
L P M
ADDER ROGRAMMING ANUAL
Example
-
ON
OFF
200.0°C
2.0°C
ON
OFF
193.0°C 195.0°C
5.0°C
ON
OFF
200.0°C
5.0°C
2.0°C
ON
OFF
195.0°C 197.0°C 200.0°C
5.0°C
2.0°C
ON
OFF
195.0°C 197.0°C 200.0°C 203.0°C 205.0°C
FC9Y-B1726
5.0°C
2.0°C
203.0°C 205.0°C
5.0°C
200.0°C
2.0°C
205.0°C 207.0°C
5.0°C
2.0°C