Three-Step Control; On/Off Control; Continuous Control In Control Circuit Rk1 - Samson TROVIS 5573 Mounting And Operating Instructions

7.6

Three-step control

The flow temperature can be controlled using a PI algorithm. The valve reacts to pulses that the
controller sends when a system deviation occurs. The length of the first pulse, in particular, de-
pends on the extent of the system deviation and the selected Proportional gain K
length increases as K
system deviation has been eliminated. The pause length between the single pulses is greatly in-
fluenced by the Reset time T
The Transit time T
Y
100 %.
Function
Control mode
7.7

On/off control

The flow temperature can be controlled, for example, by activating and deactivating a boiler.
The controller switches on the boiler when the flow temperature falls below the set point by
T = 0.5 x hysteresis . When the set point is exceeded by T = 0.5 x hysteresis , the boiler is
switched off again. The greater the value you choose for Hysteresis , the lower the activa-
tion/deactivation frequency will be. By setting the Minimum ON time , an activated boiler re-
mains switched on during this period regardless of the flow temperature fluctuations. Similarly,
a deactivated boiler will remain switched off regardless of the flow temperature fluctuations if
the Min. OFF time has been specified.
Function
Control mode
7.8

Continuous control in control circuit Rk1

The flow temperature in the control circuit Rk1 can be controlled using a PID algorithm. The
valve in control circuit Rk1 receives an analog 0 to 10 V signal. When a system deviation oc-
curs, the proportional component immediately causes the 0 to 10 V signal to change (the
greater K , the greater the change). The integral component becomes effective with time: T
P
increases). The pulse and pause lengths change continuously until the
P
(the pause length increases as T
N
specifies the time required by the valve to travel through the range of 0 to
WE
1
2.0
120 s
0 s
45 s
WE
1
5.0 °C
2 min
2 min
Configuration
CO1, 2, 4 -> F12 - 1, Rk_
KP (proportional gain) / 0.1 to 50.0
Tn (reset time) / 1 to 999 s
TV (derivative-action time) / Do not change!
TY (valve transit time) / 5, 10, 15, ... , 240 s
Configuration
CO1, 2, 4 -> F12 - 0
Hysteresis / 1.0 to 30.0 °C
Min. ON time / 0 to 10 min
Min. OFF time / 0 to 10 min
System-wide functions
increases).
N
EB 5573 EN
(the pulse
P
N
73