Danfoss VLT AQUA Drive FC 202, Руководство по программированию

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22-39 High Speed Power [HP]
Range: Function:
Size
related
*
[ 0 -
7.50 hp] To be used if parameter 0-03 Regional
Settings is set for [1] North America
(parameter not visible if [0] International is
selected).
Set power consumption at 85% speed level.
This function is used for storing values
necessary for tuning no-flow detection.
3.19.4 22-4* Sleep Mode
If the load on the system allows for stop of the motor and
the load is monitored, the motor can be stopped by
activating the sleep mode function. This is not a normal
stop command, but ramps the motor down to 0 RPM and
stops energizing the motor. When in sleep mode, certain
conditions are monitored to find out when load has been
applied to the system again.
Sleep mode can be activated either from the no-flow
detection/minimum speed detection or via an external
signal applied to 1 of the digital inputs (programmed via
the parameters for configuration of the digital inputs,
parameter group 5-1* Digital Inputs ).
To facilitate use of, for example, an electro-mechanical flow
switch to detect a no-flow condition and activate sleep
mode, the action takes place at raising edge of the
external signal applied. Otherwise, the frequency converter
would never come out of sleep mode again as the signal
would be steadily connected.
If parameter 25-26 Destage At No-Flow is set for [1] Enabled ,
activating sleep mode applies a command to the cascade
controller (if enabled) to start destaging of lag pumps
(fixed speed) before stopping the lead pump (variable
speed).
When entering sleep mode, the lower status line in the
display shows sleep mode.
See also signal flow chart, Illustration 3.63 .
There are 3 different ways of using the sleep mode
function:
•
Boost system with pressure feedback.
•
System with pressure feedback.
•
Boost system without pressure feedback.
130BA255.11
P
f
o
pSL
FC
S
FC Frequency converter
f
O
Frequency out
P
S
P system
P
SL
P setpoint
Illustration 3.66 Sleep Mode Function
In 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 for [3]
Closed loop .
2. Configure the PI controller for reference and
feedback signals.
Illustration 3.67 shows a boost system.
p (Pressure)
Time
Time
No/Low Flow
detected
P 22-45
P 22-44
Sleep mode
activated
Boost
activated
P
Boost
P
Set
P
Wake
f
Ref
f
out
(Frequency)
P
System
130BA257.10
t
1
p
System
= p
Wake
Illustration 3.67 Boost System with Pressure Feedback
Parameter Description Programming Guide
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