Threshold values and reaction time – Burkert Type 8644 User Manual
Page 112
108 - 8644/phoenix
S
YSTEM
D
ESCRIPTION
Threshold values and reaction time
If the measured value exceeds the upper threshold value (or lies below the lower threshold value), after
expiry of a set reaction time warning messages are sent via the bus (see chapter
Warning and Error Mes-
sages).
At the same time, the pressure value on the local display alternates with the message
HI (upper threshold
value) or
LO (lower threshold value). If the pressure returns to the proper range before expiry of the reaction
time, the watchdog is reset. After the next excursion outside the limits, the reaction time again runs for the
full period before warning messages are issued.
If the reaction time is set to zero, the threshold treatment is deactivated, i.e. the set threshold values are
without effect.
upper threshold value
pressure curve
reaction time t
lower threshold value
10
9
7
8
6
5
4
3
0
2
1
1
5
3
7
9
11
13
17
19
21
15
23
25
27
29
31
33
35
37
41
43
47
45
39
Watchdog activated
Watchdog activated
Watchdog expired
Watchdog activated
Watchdog reset
Watchdog reset
Watchdog expired
Warning messages are
sent to the master and
the pressure value
HI
is
displayed.
Warning messages are
sent to the master and
the pressure value
LO
is
displayed.
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