4 switching behaviuor 45, 1 standard ( cycl= 0 ) 45, 2 switching attitude linear ( cycl= 1 ) 45 – West Control Solutions KS 92-1 User Manual
Page 45: Standard 45, 4 switching behaviuor, Configuration level
4.4 Switching behaviuor
With these controllers, configuration parameter
CYCL (ConF/ Cntr/ CYCL)
can be used for matching the cycle time of 2-point and 3-point controllers. This
can be done using the following 4 methods.
4.4.1 Standard (
CyCl= 0 )
The adjusted cycle times
t1 and t2 are valid for 50% or -50% correcting varia-
ble. With very small or very high values, the effective cycle time is extended to
prevent unreasonably short on and off pulses. The shortest pulses result from ¼
x
t1 or ¼ x t2. The characteristic curve is also called “bath tub curve”
Parameters to be adjusted:
t1 : min. cycle time 1 (heating) [s]
(
PArA/ Cntr)
t2 : min. cycle time 2 (cooling) [s]
4.4.2 Switching attitude linear (
CyCl= 1 )
For heating (
Y1), the standard method (see chapter 4.4.1) is used. For cooling
(
Y2), a special algorithm for cooling with water is used. Generally, cooling is en-
abled only at an adjustable process temperature (
E.H2O), because low temperatu-
res prevent evaporation with related cooling, whereby damage to the plant is
avoided. The cooling pulse length is adjustable using parameter
t.on and is fi-
xed for all output values.
The “off” time is varied dependent of output value. Parameter
t.off is used for
determining the min “off” time. For output of a shorter off pulse, this pulse is
suppressed, i.e. the max. effective cooling output value is calculated according to
formula
t.on / ( t.on + t.off) w 100%.
Parameters to be adjusted:
E.H2O: minimum temperature for water cooling
(
PArA / Cntr)
t.on:
pulse duration water cooling
t.off: minimum pause water cooling
Configuration level
KS 90-1 / KS 92-1
45
Switching behaviuor
0,0
1,0
2,0
3,0
4,0
5,0
6,0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
Controller output [%]
re
lat
ive
cycle
duration
T / T
1
t1
2 x
t1
3 x
t1
4 x
t1