46
9.10
Operation at minimum frequency
CONFIG FMIN
f => fmin
Possible setting
: f->0 or f->f
min
f->0:
After reaching the required pressure the frequency will go down to the selected
MINIMUM FREQUENCY and the HYDROVAR will keep running for the selected “STOP DELAY”
time (see next parameter). After this time the HYDROVAR will stop automatically.
f->f
min
: With these setting the pump will never stop automatically. Only the frequency will go
down to the selected MINIMUM FREQUENCY. To stop the pump you have to open the
external ON/OFF (terminals X1/4 and 5) or press the
Ð
button.
Applications: circulation systems
The setting f->fmin can overheat the pump, when there is no flow through
the pump. => bypass line for circulation pumps!
Press the
¾
button to change to the next parameter
9.11
Delay time to shut off below minimum frequency
STOP-DELAY FMIN
5 s
Possible setting between 0 and 100s
•
After running the pump for this selected time at minimum frequency, the pump will stop, if
parameter CONFIG. FMIN is set to f
->
0
•
If the limit of the parameter ENABLE SEQUENCE CONTROL is exceeded and the relay
configuration is set to SIMPLE MULTICONTROLLER (see chapter 9.20), the pump running
relay (X2/4-5-6) will be closed after running the pump for this selected time.
Press the
¾
button to change to the next parameter
9.12
Boost
BOOST
5.0 %
Setting of the motor starting voltage in % of rated
voltage (0 - 25% of maximum input voltage is possible)
This value determines the characteristics of the voltage/frequency curve.
In particular, it refers to the voltage increase during the motor starting stage as a percentage
of the nominal voltage. Take care that settings are kept as low as possible so that the motor
does not become thermally overloaded at lower frequencies.
If the boost is set too low, a failure (OVERLOAD) may occur because the starting-current is too
high.
Press the
¾
button to change to the next parameter
NOTICE:
Problems with shut off the pump at 0 demand (too small or no pressure tank)
may be solved by exceeding the required value during this delay-time.
