Burkert Type 1110 - Handbuch (Seite 34)

32 - 1110
DIGITAL INDUSTRIAL CONTROLLER
english
Adjustable parameter:
T+: Period of the 2-point PWM signal
Options:
Imp. no: Use of a standard valve.
The 2-point PWM signal is output via relay1
Imp. yes: Use of a pulse valve. 2 relays are used for output in this case.
Relay 1 is energised with the rising edge of the 2-point PWM signal,
while relay 2 is energised with its falling edge. A pulse valve can be
actuated in this way. The valve’s pick-up winding is triggered with
relay 1, while its drop-out winding is triggered with relay 2.
Function block 17: 3-point PWM signal
3-point Output
The 3-point PWM output is a combination of two 2-point PWM outputs. One PWM
output controls the output relay 1 (Output relay, heat) dependent on CO
h
, while the
other PWM output controls the output relay 2 (Output, cool) dependent on CO
k
.
Each of the two outputs is subordinated to a PID algorithm within the controller. The
following diagram shows the principle of the controller characteristic for the 3-point
output:
The Output, Heat period, T+, and the Output, Cool period, T-, can be set separately
of one another.
In addition, the amplification factors for both controllers (heat / cool) can be
separately adjusted. The reset time Tr (I-portion of the controller) and the derivative
action time Td (D-portion of the controller) are the same for both controllers.
Figure 19: 3-point output
Setpoint SP Actual value PV
Heat Cool
100 %
Controlled
variable CO
Characteristic for
P-controller