- 50 -
Upper alarm: Variation width per unit time [
∆
t]
(PV2 - PV1) is at plus side.
Lower alarm: Variation width per unit time [
∆
t]
(PV2 - PV1) is at minus side.
Unit time [
∆
t] = measuring interval (approx. 0.1sec) x
measuring count (1 to 20)
∆
t
Variation width
(PV2 - PV1)
-
+
D
U
Upper alarm
Lower alarm
Alarm value of D *
Alarm value of U
Rate-of-change alarm
Difference in measured value (absolute value)
≥
alarm value: diff upper alarm activated
Difference in measured value (absolute value)
≤
alarm value: diff lower alarm activated
(Diff upper alarm)
Alarm activated
Alarm value
Difference
(Absolute
value)
Alarm activated
Alarm value
Difference
(Absolute
value)
(Diff lower alarm)
Differential alarm