22-22 Low Speed Detection
Option:
Function:
minimum as required for the normal low speed
detection.
When this option is selected, the frequency
converter creates a pressure pulse (boost of the
pressure) when the feedback is within the
range defined in
parameter 7-39 On Reference
Bandwidth
for a time period defined in
parameter 22-40 Minimum Run Time
or longer.
Parameter 22-45 Setpoint Boost
adjusts the
height of the pulses.
Parameter 22-46 Maximum Boost Time
defines
the maximum length of the pulse.
Refer to
Cascade Controller Options MCO
101/102 Operating Instructions
for more
information about the cascade controller.
NOTICE
Ensure that the system can withstand
the boost pressure.
22-23 No-Flow Function
Common actions for low-power detection and low-speed
detection (individual selections not possible).
Option:
Function:
[0]
*
Off
NOTICE
Do not set
parameter 14-20 Reset Mode
,
to
[13] Infinite auto reset
, when
parameter 22-23 No-Flow Function
is set
to
[3] Alarm
. Doing so causes the
frequency converter to continuously
cycle between running and stopping
when a no-flow condition is detected.
NOTICE
Disable the automatic bypass function
of the bypass if the frequency converter
is equipped with a constant-speed
bypass with an automatic bypass
function starting the bypass if the
frequency converter experiences a
persistent alarm condition, and
[3]
Alarm
is selected as the no-flow
function.
[1]
Sleep
Mode
The frequency converter enters sleep mode
and stops when a no-flow condition is
detected. See
parameter group 22-4* Sleep
Mode
for programming options for sleep
mode.
[2]
Warning
The frequency converter continues to run, but
activates a no-flow warning
(warning 92,
NoFlow)
. A digital output or a serial communi-
22-23 No-Flow Function
Common actions for low-power detection and low-speed
detection (individual selections not possible).
Option:
Function:
cation bus can communicate a warning to
other equipment.
[3]
Trip
The frequency converter stops running and
activates a no-flow alarm
(alarm 92, NoFlow)
. A
frequency converter digital output or a serial
communication bus can communicate an
alarm to other equipment.
[4]
Stop and
Trip
22-24 No-Flow Delay
Range:
Function:
10 s
*
[1 - 600 s] Set the time that low power/low speed must
stay detected to activate signal for actions. If
detection disappears before the timer runs
out, the timer is reset.
22-26 Dry Pump Function
Select the action for dry-pump operation.
Option:
Function:
[0]
*
Off
Parameter Description
VLT
®
AQUA Drive FC 202
180
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MG20OB02
3
3
Summary of Contents for VLT AQUA Drive FC 202
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