Herz pelletstar 10, Руководство по эксплуатации

Страница: 78 / 96

8 Terms and definitions
78 Betriebsanleitung_PS_10_60_Touch_Englisch_V1.3
The line in the diagram results due to the following parameters (see Figure 8.1):
Figure 8.1: Settings
– external requirement
Is there for example an analog requirement with an current signal of 12 mA, a temperature of 60°C is
registered at the heat supplier, provided that the digital requirement (= external must temperature) is not
higher.
At the input of the external requirement module a current signal between 4 and 20 mA should lie on,
because a current signal is in comparison with a voltage signal insensitive to electromagnetic disturbances
and voltage losses on the cables. With an internal resistor (500 Ohm) a current signal is converted into a
voltage signal.
External requirement
module
500 Ohm
Input signal
= current signal
Current signal in mA
An
alog
mu
st t
emp
e
ratu
re
in °C
Figure 8.2: Analog must temperature as a function of the applied current signal of the external
requirement
Figure 8.3: Input signal of the external requirement module