ELECTRONIC CIRCULATOR FOR SOLAR THERMAL SYSTEMS - Art. S167
FI.S167.EN.C - 03/2023
Icma SpA - Via Garavaglia, 4 - 20012 Cuggiono (MI) ITALY Tel: +39 02 97249134 - +39 02 97249135 - www.icmaspa.it - [email protected]
Icma SpA - Via Garavaglia, 4 - 20012 Cuggiono (MI) ITALY Tel: +39 02 97249134 - +39 02 97249135 - www.icmaspa.it - [email protected]
14
15
PWM Input Signal (%)
Pump Status
0
The pump switches to non-PWM mode (normal mode), and the default
system will have no PWM signal input.
<10
The pump runs at the highest velocity
10~84
The pump curve will drop from the highest to the lowest
85~91
The pump runs at the lowest velocity
91~95
If the velocity variance point of input signal fluctuates, then it will block
the start and stop of the pump according to the principle of magnetic
hysteresis
96~99
Stand-by, the pump stops
100
The pump switches to non-PWM mode (normal mode), and the default
system will have no PWM signal input.
•
In the area of high duty-cycle PWM signal, when the input signal fluctuates in the critical point, there will be a delay
area to prevent frequent stops and start of the pump.
•
In area of low duty-cycle PWM signal, the pump runs at high velocity for the sake of system safety. For instance, when
the signal cable of gas boiler system is damaged, the pump will continue to run at the maximum rotational speed
and transfer heat through the main heat exchanger. This is also applicable to the heat pump, ensuring continuous
heat transfer in the case of signal cable of the pump is damaged and system safety is guaranteed. ·When PWM input
signal is 0% or 100%, the pump will switch to non-PWM mode (normal mode), and the default system will have no
PWM signal input.
8.3 PWM Input Signal
NOTE
This system is adaptive to the automatic switching of PWM and non-PWM mode.
When there is PWM signal input, the system will enter PWM mode.
