Determining The System Parameters For 2/3-Step Controllers (When Main Control Byte 1, Bit 2 = 0) - Siemens SIMATIC S5 Manual

4.6 Determining the System Parameters for 2/3-Step
Controllers (when Main Control Byte 1, Bit 2 = 0)
The heating and cooling curves of temperature-controlled systems are plotted with a recorder (see
Fig. 4.6/1).
The procedure is as follows:
– main control byte 1, bit 2 = 0
– entry of non-critical control parameters
T
A
K
R
T , T
N D
Upper limit of the control zone = 30 C
Lower limit of the control zone = 30 C
HKV = 100 % (for 3-step controllers)
– Enter the setpoint temperature
The module switches the heating on.
– Wait until the actual value has "settled"
Note: the actual value does not need to have reached the setpoint.
– Enter setpoint temperature = 1 C
The module switches the cooling on.
Note: and only required with 3-step controllers.
The parameters are then obtained from the curve:
T = delay time (in s)
U
S = maximum slope of the cooling curve (in C/s)
K
S = maximum slope of the heating curve (in C/s)
H
IP244
C79000–B8576–C860–02
= 5 s (numerical value 5000)
= 1 (numerical value 100)
= 0
.
.
.
Notes on Controller Settings
4–137