Endress+Hauser Topclean S CPC30, Руководство по эксплуатации

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6 Commissioning Topclean S
86 Hauser
6.6.13 Set up 2 – Limit switch
The transmitter CPM153 has several possibilities for assigning a relay contact. The limit contactor
can be assigned to a switch-on and switch-off point, as well as a pickup and dropout delay. In
addition, an error message can be generated when an alarm threshold is set. You can trigger cleaning
in connection with this error message (see Error/Contact Assignment, page 65). These functions
can be used for both, pH/redox and temperature measurement.
The contact states of any relay or fault signalling contact are illustrated in fig. 45:
With increasing measured values, switch-on point > switch-off point (maximum function):
– The relay contact closes after the switch-on point t
1
is exceeded and the pickup delay (t
2 -
t
1
)
expires.
– When the alarm threshold t
3
is reached and the alarm delay (t
4
- t
3
) has expired, the fault
signalling contact switches.
– With falling measured values, the fault signalling contact reopens when the alarm threshold is
undershot at t
5
. The corresponding error message is deleted.
– The relay contact opens again after the switch-off point is reached at t
6
and the dropout delay has
elapsed (t
7
- t
6
).
With falling measured values, switch-on point < switch-off point (minimum function):
– The relay contact closes after the measured values have fallen below the switch-on point t
1
and
the pickup delay has expired (t
2
- t
1
).
– When the alarm threshold t
3
is reached and the alarm delay (t
4
- t
3
) has expired, the fault
signalling contact switches.
– With increasing measured values, the fault signalling contact reopens when the alarm threshold
t
5
is exceeded. The corresponding error message is deleted.
– The relay contact opens again after the switch-off point has been reached at t
6
and the dropout
delay has elapsed (t
7
- t
6
).
C07-CPM153xx-05-06-00-en-006.eps
ƒig. 45: Diagram of the relationship between switch-on and switch-off points and on and off delay
!
Note!
If the pickup and dropout delays are set to 0 s, the switch-on and switch-off points are the switching
points of the contacts.
Switch-on point
Switch-on point
Switch-off point
Switch-off point
Alarm threshold
Measured value
Contact ON
Contact ON
Alarm ON
Alarm OFF
Contact OFF
Contact OFF
Switch-on point > switch-off point: Maximum function
Switch-on point < switch-off point: Minimum function
on
delay
off
delay