Mycom S CPM 153
6 Start-up
Hauser
67
6.5.13
Set up 2 – Limit switch
The Mycom S has several possibilities for assigning a relay contact. The limit switch 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 44).
These functions can be used both for pH/redox and temperature measurement.
To illustrate the contact states of any relay or fault signalling contact, refer to Fig. 26 for
the
contact states:
Switch-on point > switch-off point (with increasing measured values):
– the relay contact closes at after the switch-on point t
1
is exceeded and the pickup
delay (t
2
t
1
) expires.
– Then the alarm threshold t
3
is reached and the error delay (t
4
- t
3
) also expires, the fault
signalling contact switches.
– With returning measured values, the fault signalling contact reopens when the alarm
threshold is undershot at t
5
. The appropriate error message is deleted.
– The relay contact opens again after the switch-off point is reached at t
6
and the drop-
out delay has elapsed (t
7
- t
6
).
!
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.
•
You can make identical settings for a minimum function similar to the maximum func-
tion.
Fig. 26:
Diagram of the relationship between switch-on and switch-off points and on and off delay
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:
Switch-on point < switch-off point:
C07-CPM153xx-05-06-00-en-006
on
delay
off
delay