ACS Precont S, Technical Manual, Page: 13 / 28

Precont S
page 13 of 28
PNP – switching output
The switching function realizes a stable switching condition,
independent from system conditioned pressure fluctuations
around the adjusted set point.
It can also be used for realizing a pressure controlled
two-position control.
The switching range is determined separately by the
switch point –
SP
– and hysteresis –
HyS
–
for the respective switching output.
For the switch point as well as for the hysteresis an
arbitrary value referring to the display scaling can be input.
The switch back point result from switch point deducting
hysteresis, as equation SP – Hys.
There is no default minimum value for hysteresis, that
means the distance between switch resp. switch back point.
The working principle can be set separately for each switching output to:
open-circuit principle resp. no normally open or to closed-circuit principle resp. nc normally closed
The switching output S1 can be also used for error indication function alternatively to the limit value function.
Doing this a switching action happens, if the output signal becomes higher than 20mA/10V resp. lower than
4mA/0V.
Damping
The damping influences the reaction speed of
display, output signal and switching output at a
change of the pressure.
The behaviour of display and output signal follows an
exponential characteristic with the damping time constant  .
Within the time period  the output signal increases
respectively by 63% of the existing deviation.
With 99,3%, the end value is nearly achieved after 5  .
At the variants A / B / E / F the damping can be adjusted from 0...60 seconds in 100 steps from 0...100,
whereby one step equals 0,6 seconds.
The set time (value x 0,6 seconds) equals 5  .
At the variants type C and G the damping can be adjusted from 0...6 seconds in 10 steps from 0...10, whereby
one step equals 0,6 seconds.
The set time (value x 0,6 seconds) equals 5  .
Function scheme
0
1
0
1
p
t
SP
SP-Hys
No
Nc