Commissioning
Liquisys M CUM223/253
48
Hauser
6.4.6
Relay contact configuration
To use the RELAY function group, you need a relay board which is not part of the basic
version.
The following relay contacts can be selected and configured as desired (max. four contacts,
depending on options installed):
• Limit contactor for measured turbidity value: R2 (1)
• Limit contactor for temperature: R2 (2)
• PID controller: R2 (3)
• Timer for cleaning function: R2 (4)
• Chemoclean function: R2 (5)
Limit contactor for measured turbidity value and temperature
The transmitter has different ways of assigning a relay contact.
Switch-on and switch-off points and pick-up and drop-out delays can be assigned to the limit
contactor. In addition, you can configure an alarm threshold to output an error message and
to start a cleaning function in conjunction with this.
These functions can be used both for turbidity measurement and for temperature
measurement.
Please refer to Fig. 25 for a clear illustration of the relay contact states.
• When the measured values increase (maximum function), the relay contact is closed as of
t
2
after the switch-on point (t
1
) has been overshot and the pick-up delay has elapsed
(t
2
- t
1
).
The alarm contact switches if the alarm threshold (t
3
) is reached and the alarm delay
(t
4
- t
3
) has also elapsed.
• When the measured values decrease, the alarm contact is reset when the alarm threshold
(t
5
) is undershot as is the relay contact (t
7
) after the drop-out delay (t
7
- t
6
).
• If the pick-up and drop-out delays are set to 0 s, the switch-on and switch-off points are
also switch points of the contacts.
Settings can also be made for a minimum function in the same way as for a maximum
function.
C07-CxM2x3xx-05-06-00-xx-003.eps
Fig. 25:
Illustration of the alarm and limit value functions
A
B
Switch-on point > switch-off point: Max. function
Switch-on point < switch-off point: Min. function
1
2
3
4
Alarm threshold
Switch-on point
Switch-off point
Contact ON
5
6
7
Alarm ON
Alarm OFF
Contact OFF
t
1
t
1
t
2
t
2
t
3
t
3
t
4
t
4
t
5
t
5
t
6
t
6
t
7
t
7
t
t
B
1
2
3
3
2
1
4
5
6
7
4
5
6
7
A
