Danfoss VLT FC 103 Programming Manual page 136

Parameter Description
3.17.4 22-5* End of Curve
The End of Curve conditions occur when a pump is
yielding a too large volume to ensure the set pressure.
This can occur if there is a leakage in the distribution pipe
system after the pump causing the pump to operate at the
end of the pump characteristic, valid for the max. speed
set in 4-13 Motor Speed High Limit [RPM] or 4-14 Motor
Speed High Limit [Hz].
In case the feed back is 2.5% of the programmed value in
20-14 Maximum Reference/Feedb. (or numerical value of
20-13 Minimum Reference/Feedb. whichever is highest)
below the set point for the desired pressure for a set time
(22-51 End of Curve Delay), and the pump is running with
max. speed set in 4-13 Motor Speed High Limit [RPM] or
4-14 Motor Speed High Limit [Hz], - the function selected in
22-50 End of Curve Function will take place.
It is possible to get a signal on one of the digital outputs
by selecting End of Curve [192] in parameter group 5-3*
Digital Outputs and/or parameter group 5-4* Relays. The
signal will be present, when an End of Curve condition
occurs and the selection in 22-50 End of Curve Function, is
different from Off. The end of curve function can only be
used when operating with the built-in PID controller
(Closed loop in 1-00 Configuration Mode).
22-50 End of Curve Function
Option: Function:
[0] Off End of Curve monitoring not active.
*
[1] Warning The frequency converter will continue to run, but
activate a End of Curve warning [W94]. A
frequency converter digital output or a serial
communication bus can communicate a warning
to other equipment.
[2] Alarm The frequency converter will stop running and
activate a End of Curve alarm [A 94]. A frequency
converter digital output or a serial communi-
cation bus can communicate an alarm to other
equipment.
NOTE
Automatic restart will reset the alarm and start the system
again.
NOTE
Do not set 14-20 Reset Mode, to [13] Infinite auto reset,
when 22-50 End of Curve Function is set to [2] Alarm. Doing
so will cause the frequency converter to continuously cycle
between running and stopping when a End of Curve
condition is detected.
®
VLT Refrigeration Drive Programming Guide
NOTE
If the frequency converter is equipped with a constant
speed bypass with an automatic bypass function that starts
the bypass if the frequency converter experiences a
persistent alarm condition, be sure to disable the bypass's
automatic bypass function, if [2] Alarm or [3] Man. Reset
Alarm is selected as the End of Curve Function.
22-51 End of Curve Delay
Range:
10 s
3.17.5 22-6* Broken Belt Detection
The Broken Belt Detection can be used in both closed and
open loop systems for pumps, fans and compressors. If the
estimated motor torque is below the broken belt torque
value (22-61 Broken Belt Torque) and the frequency
converter output frequency is above or equal to 15 Hz, the
broken belt function (22-60 Broken Belt Function) is
performed
22-60 Broken Belt Function
Selects the action to be performed if the Broken Belt condition is
detected
Option:
[0]
[1]
[2]
NOTE
Do not set 14-20 Reset Mode, to [13] Infinite auto reset,
when 22-60 Broken Belt Function is set to [2] Trip. Doing so
will cause the frequency converter to continuously cycle
between running and stopping when a broken belt
condition is detected.
®
MG16H102 - VLT is a registered Danfoss trademark
Function:
[0 - 600 When an End of Curve condition is detected, a
*
s] timer is activated. When the time set in this
parameter expires, and the End of Curve
condition has been steady in the entire period,
the function set in 22-50 End of Curve Function
will be activated. If the condition disappears
before the timer expires, the timer will be reset.
Function:
Off
*
Warning The frequency converter will continue to run, but
activate a Broken Belt Warning [W95]. A
frequency converter digital output or a serial
communication bus can communicate a warning
to other equipment.
Trip The frequency converter will stop running and
activate a Broken Belt alarm [A 95]. A frequency
converter digital output or a serial communi-
cation bus can communicate an alarm to other
equipment.
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