Danfoss VLT AutomationDrive FC 361, Руководство по программированию

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2) Systems where the integrated PI controller is used for
controlling pressure or temperature, for example boost
systems with a pressure feedback signal applied to the
frequency converter from a pressure transducer.
1. Set parameter 1-00 Configuration Mode to [3]
Process .
2. Configure the PI controller for reference and
feedback signals.
e30bg833.10
P
f Out
p
Set
FC
P
System
Illustration 4.51 Sleep Mode Function
Digital input
enabled
p(Pressure)
Time
Time
P22-45 x
P22-44 x
Sleep mode
activated Boost
activated
P
Boost
P
Set
P
Wake-up
f
Ref
f
out
(Frequency)
P
System
e30bg836.10
p
System
= p
Wake-up
P
Set
P
Set
P
Ref
f
O ut
Illustration 4.52 Sequence Diagram
If the difference between pressure reference and feedback
is smaller than the threshold, the boost function activates,
which means the frequency converter increases the
setpoint for pressure to ensure a slight overpressure in the
system (the boost is set in
parameter 22-45 Setpoint Boost ).
The feedback from the pressure transducer is monitored.
When this pressure has dropped with a set percentage
below the normal setpoint for pressure (P
set
), the motor
ramps up again. The pressure is then controlled for
reaching the set value (P
set
).
External PI controller or manual control
( parameter 1-00 Configuration Mode : Open loop)
Internal PI controller
( parameter 1-00 Configuration Mode : Closed loop)
Sleep mode activated Wake up Sleep mode activated Wake up
Pressure/temperature
(transmitter connected)
– – Yes Yes
Output frequency Yes Yes – –
Boost function – – Yes –
Sleep mode enable External DI signal ( parameter group 5-1* Digital Inputs )
Table 4.21 Configuration Overview
The goal of the boost function is to keep the frequency converter in sleep mode as long as possible to avoid cycling the
motor on and off frequently, and also keep the controlled system variable within the acceptable range. Boost is only to be
used when
parameter 1-00 Configuration Mode is set to [3] Process , and the integrated PI controller is used.
NOTICE
Sleep mode is not active when local reference is active (set speed manually with the navigation keys on the LCP). See
parameter 3-13 Reference Site .
Does not work in hand-on mode. Carry out auto set-up in open loop before setting input/output in closed loop.
Parameter Descriptions Programming Guide
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