wtw TresCon UNO A111, Operating Manual

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TresCon UNO Operation
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Fig. 5-7 Relay output of the pulse-width controller
The cycle duration (T) is made up of the turn-on and turn-off switching
duration (t
on
, t
off
) of the relay together. While the selected cycle dura-
tion (T) remains constant, the turn-on duration (t
on
) changes depen-
ding on the measured value and, with it, the pulse width (v). The pulse
width can be set from 0 % to 100 %.
v = (t
on
/ T) * 100 %
v = pulse width, T = cycle duration, t
on
= turn-on duration

If the measured value is at the end of the proportional range ( End
value ), the turn-on duration t
on
is long, and the turn-off duration
short. The relay operates for a longer period of time.

If the measured value is at the beginning of the proportional range
(
Start value ), the turn-on duration t
on
is short, and the relay operates
for a correspondingly shorter period.
T
Time [s]
Relay
Off
On
t
On
t
Off