Endress+Hauser Liquisys M CLM253 - Timer for Cleaning Function

Liquisys M CLM223/253 Commissioning
Endress+Hauser 57
A
1
0
T
t [s]
A
t [s]
t
1
t
2
t
1
1
0
T
1
T
2
A0025219
 32 Signal of a pulse-length modulated controller contact (left) and of a pulse frequency-modulated controller
contact (right)
Contact: 1 = on, 0 = off T Period
Time (s): t
1
= t
on
t2 = t
off
T1 T2 Impulse period length ( 1/T
1
and 1/T
2
)
Constant controller
The controller can also control the second analog current output (if provided). This is
configured in fields R237 and O2.
Control characteristic for direct and inverse control action
You can choose between two control characteristics in the R236 field:
• Direct control action = maximum function
• Inverse control action = minimum function
X
W
X
W
– X
W
– X
W
100 %
100 %
Y
Y
A
B
A0025222
 33 Control characteristic of a proportional controller with direct and inverse control action
A Direct = maximum function
B Inverse = minimum function
XW Control deviation
Y Current output signal = controller actuating variable
Timer for cleaning function
This function includes a simple cleaning option. You can set the time interval after which
cleaning should start. Therefore you can only select a constant interval sequence.
Other cleaning functions are available for selection in conjunction with the Chemoclean
function (device version with four contacts required, see the "Chemoclean function"
section).
The timer and Chemoclean do not work independently of one another. While one of
the two functions is active, the other cannot be started.