Danfoss VLT, Инструкция по эксплуатации

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20-94 PID Integral Time
Range: Function:
20.00 s* [0.01 - 10000.00 s] Over time, the integrator accumulates a contribution to the output from the PID controller as long
as there is a deviation between the reference/setpoint and feedback signals. The contribution is
proportional to the size of the deviation. This ensures that the deviation (error) approaches zero.
Quick response on any deviation is obtained when the integral time is set to a low value. Setting it
too low, however, may cause the control to become unstable.
The value set, is the time needed for the integrator to add the same contribution as the proportional
part for a certain deviation.
If the value is set to 10,000, the controller will act as a pure proportional controller with a P-band
based on the value set in par.20-93
PID Proportional Gain
. When no deviation is present, the output
from the proportional controller will be 0.
22-21 Low Power Detection
Option: Function:
[0] * Disabled
[1] Enabled If selecting Enabled, the low power detection commissioning must be carried out in order to set the
parameters in group 22-3* for proper operation!
22-22 Low Speed Detection
Option: Function:
[0] * Disabled
[1] Enabled Select Enabled for detecting when the motor operates with a speed as set in par.4-11 Motor Speed
Low Limit [RPM] or par.4-12 Motor Speed Low Limit [Hz] .
22-23 No-Flow Function
Option: Function:
Common actions for low power detection and low speed detection (Individual selections not possi-
ble).
[0] * OFF
[1] Sleep Mode
[2] Warning Messages in the Local Control Panel display (if mounted) and/or signal via a relay or a digital output.
[3] Alarm The adjustable frequency drive trips and the motor stays stopped until reset.
22-24 No-Flow Delay
Range: Function:
10 s* [1 - 600 s] Set the time. Low Power/Low Speed must remain detected to activate signal for actions. If detection
disappears before the timer runs out, the timer will be reset.
22-26 Dry Pump Function
Option: Function:
Low Power Detection must be Enabled (par.22-21 Low Power Detection ) and commissioned (using
either par. 22-3*, No Flow Power Tuning , or par. 22-20 Low Power Auto Set-up ) in order to use dry
pump detection.
[0] * OFF
[1] Warning Messages in the Local Control Panel display (if mounted) and/or signal via a relay or a digital output.
[2] Alarm The adjustable frequency drive trips and the motor stays stopped until reset.
VLT ® HVAC Drive Instruction Manual
6 How to program the adjustable frequency
drive
MG.11.A9.22 - VLT ® is a registered Danfoss trademark
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