Riello Dialog Plus 300, Инструкция по эксплуатации

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14
control siGnals
The pump must be controlled by a low voltage, digital,
PWM (Pulse Width Modulation) signal. Pump speed
varies with the input signal as shown in the "PWM input
signal"
figure.
The following is a description of the main characteristics
that the PWM signal generated by the controller must
have.
b
Make sure that the characteristics of your control-
ler’s PWM signal conform to the following require-
ments. Signals with different characteristics can
cause irreparable damage to the pump’s on-board
electronic circuits.
low voltage, digital, pWm signal
The square wave PWM signal covers a frequency band
of 100 to 4,000 Hz. The PWM signal is used to control
pump speed.
duty cycle
example interpretation
T = 2 ms (500 Hz) UiH = 4-24 V
t = 0.6 ms UiL ≤ 1 V
d % = 100 x 0.6 / 2 = 30 % IiH ≤ 10 mA (depending
on UiH)
Example
T
U
iH
U
iL
t
T Period
d Duty cycle (t/T)
UiH Input signal high voltage level
UiL Input signal low voltage level
IiH Input signal current intensity