Separate Pi Functions - Danfoss AK-PC 781A User Manual

Configuration - continued

Separate PI functions

1. Select PI functions
2. Select actual PI-function
Define the required names
3.
and values attached to the
function
AK-PC 781A
In our example we do not use
this function, so the display
has been included for your
information only.
Capacity controller RS8HE202 © Danfoss 2017-07
3 - General PI Control
The function can be used for optional regulation.
Adjust for each regulation
• Show on overview
• Name
• Quick settings
Here is a list of suggestions for PI regulations:
• Control mode: Off, Manual or Auto
• Control type: P or PI
• External DI ctrl: Adjusted to On if there is an external switch
that can start/stop the regulation.
• Input type: Choose which signal the regulation shall receive:
Temperature, pressure, pressure converted to temperature,
, voltage signal, Tc, Pc, Ss, Sd etc.
• Reference: Either fixed or signal for the variable reference::
Choose between: : Non, temperature, pressure, pressure
converted to temperature, voltage signal, Tc, Pc, Ss, DI etc..
• Setpoint: If fixed reference is choosen
• Reading the total reference
• Output. Here you select the outlet function (PWM = pulse
width modulated (fx AKV valve)), Stepper signal for a step-
per motor or voltage signal.
• Alarm mode: Choose whether an alarm shall be attached to
the function. If it is set to ON, alarm texts and alarm limits
can be entered.
• Advanced ctrl. settings:
• Ref. X1, Y1 and X2,Y2: Points that define and limit the
variable reference
• PWM period time: Period during which the signal has
been on and off.
• Kp: Amplification factor
• Tn: Integration time
• Filter for reference: Duration for smooth changes to the
reference
• Max. error: Maximum permissible fault signal at which the
integrator remains in the regulation
• Min. control output: Lowest permitted output signal
• Max. control output: Maximum permitted output signal
• Start up time: Time at startup at which the output signal is
force-controlled
• Startup output: The output signal size at the startup time.
• Stop output signal. Size of the output signal when regula-
tion is off.
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