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22-45 Setpoint Boost

Range:

Function:

0.0
%

[-100.0 -
100.0 %]

Only to be used if

1-00 Configuration Mode

, is set

for Closed Loop and the integrated PI controller is
used. In systems with e.g. constant pressure
control, it is advantageous to increase the system
pressure before the motor is stopped. This will
extend the time in which the motor is stopped
and help to avoid frequent start/stop.
Set the desired over pressure/temperature in
percentage of set point for the pressure (Pset)/
temperature before entering the Sleep Mode.
If setting for 5%, the boost pressure will be
Pset*1.05. The negative values can be used for e.g.
cooling tower control where a negative change is
needed.

22-46 Maximum Boost Time

Range:

Function:

60 s

[0 - 600
s]

Only to be used if

1-00 Configuration Mode

is set

for Closed Loop and the integrated PI controller is
used for controlling the pressure.
Set the maximum time for which boost mode will
be allowed. If the set time is exceeded, Sleep
Mode will be entered, not waiting for the set
boost pressure to be reached.

22-47 Sleep Speed [Hz]

Range:

Function:

0.0 s

[0.0 - 400.0 s] Set the speed below which the frequency

converter will go into Sleep Mode.

3.15.2 22-6* Broken Belt Detection

The Broken Belt Detection can be used in both closed and
open loop systems for pumps and fans. If the estimated
motor torque (current) is below the broken belt torque
(current) value (

22-61 Broken Belt Torque

) and the frequency

converter output frequency is above or equal to 15Hz,

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:

Function:

[0]

Off

[1]

Warning The frequency converter will continue to run, but

activate a Broken Belt Warning [W95]. A drive
digital output or a serial communication bus can
communicate a warning to other equipment.

[2]

Trip

The frequency converter will stop running and
activate a Broken Belt alarm [A 95]. A drive digital
output or a serial communication bus can
communicate an alarm to other equipment.

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.

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] Trip is selected as the Broken Belt
Function.

22-61 Broken Belt Torque

Range:

Function:

10 %

[5 - 100 %] Sets the broken belt torque as a percentage

of the rated motor torque.

22-62 Broken Belt Delay

Range:

Function:

10 s

[0 - 600 s] Sets the time for which the Broken Belt

conditions must be active before carrying out
the action selected in