Pump Forced Operation; External Request For Heat Demand; Control Principle - Samson 5757-7 Mounting And Operating Instructions

Functions
The yellow LED blinks slowly if the flow temperature is reduced due to the Return flow tem-
perature limitation function
Function
F11 – Return flow temperature sensor
Parameter
P13 – Max. return flow temperature
P14 – Kp Return flow temperature limitation
P15 – Tn Return flow temperature limitation
6.6

Pump forced operation

A deactivated circulation pump is forced-operated every 24 hours for one minute. This func-
tion is disenabled by selecting F10 - 0 or F09 - 1.
Functions
F09 – Function of switching output
F10 – Anti-block protection of pump
6.7

External request for heat demand

The controller with electric actuator can issue a heat demand to a higher-level controller
over the binary output BO in rated or reduced operation. In this case, a coupling relay
(contactor relay with floating contact) must be used to adapt the electrical connection.
This function is only possible when the switching output is not configured as a pump output.
Function
F09 – Function of switching output
6.8

Control principle

The controller with electric actuator functions with a PI algorithm (three-point stepping con-
trol). The valve reacts to pulses which the actuator receives from the digital controller when a
system deviation occurs. In particular, the length of the first pulse depends on the system de-
viation and the selected gain Kp flow temperature control (P09) (the pulse length increases as
the Kp rises). Pulse lengths and intervals change until the system deviation is zero again. The
interval between individual pulses is influenced considerably by the reset time Tn flow tem-
perature control (P10) (the interval time increases as the Tn rises).
The valve transit time Ty actuator transit time for valve travel (P11) reflects the time that the
25
EB 5757-7 EN
WE Configuration
1 F11 - 1
WE Range of values
50 °C 10 to 90 °C
1.0 0.1 to 50.0
400 s 0 to 999 s
WE Configuration
0 F09 - 0
1 F10 - 1
WE Configuration
0 F09 - 1