![background image](http://html1.mh-extra.com/html/danfoss/vlt-3006/vlt-3006_product-manual_3613657098.webp)
97
MG.30.A7.02 - VLT
®
is a registered Danfoss trademark
Parameter description
2.. References and limits
225 (version 3.11)
Output frequency-
dependent switch
frequency
(output.sw.freq.)
Value:
Disable (DISABLE)
[0]
High switching frequency at
low speed
[1]
(HIGH CARR @LO)
✭
Low switching frequency at
low speed
[2]
(LOW CARR @LO)
Description of choices:
Disable: This gives a fixed switching
frequency. This is to be chosen, when
using LC filter (set par. 224 to 4.5 kHz).
High switching frequency at low speed:
This is to be chosen for variable torque.
The function is not available for VLT 3060-
3250.
0-50% of rated output frequency is
switching frequency = data for par. 224.
50-100% of rated output frequency
reduces the switching frequency to 4.5
kHz. The function can reduce the acoustic
motor noise.
Low switching frequency at low speed: At
low output frequency and current the
switching frequency starts at 1.1 kHz.
From 8 Hz the switching frequency
increases to 4.5 kHz. The function
improves the motor stability.
Value
0.5 Hz-f
RANGE
✭
3 H
Z
Function:
Here the frequency at which the external
brake is to be released via Relay 01/04 is
selected.
Description of choices:
The electrome-
chanical brake must hold the motor until
the selected frequency is reached, after
which the brake is released (voltage
impressed via a relay).
If the frequency with connected start
signal comes below the selected value,
the voltage to the brake is removed and it
again becomes active.
230
Brake cut-out frequency
(Brake of freq.)
Function:
Here the frequency at which the
external brake is to be activated by stop
via Relay 01/04 is selected.
Description of choices:
The electrome-
chanical motor brake must first be acti-
vated (voltage removed) when the fre-
quency during ramp-down reaches the set
value.
231
Brake cut-in frequency
(Brake on freq.)
Value
0.5 Hz-f
RANGE
✭
3 H
Z
Value
0.0
✭
0.5
X
I
MAG
Function:
Here the minimum current value
to release the brake is selected.
Description of choices:
The brake is
released/kept open (voltage impressed via
a relay) when the minimum current value is
reached. This function is not active until
expiry of the time in para. 233.
232
Current, Minimum value
(Curr. min value)
Value
0.00 - 1.00 sec.
✭
0,10 sec.
233
Current, Delay time
(Curr .dlay. time)
Function:
Here the delay time for current
monitoring is selected (in para. 232).
Description of choices:
The brake is
activated (de-energized) if the motor
current has not reached the value set in
par. 232 after the time delay has run out.
If 0.0 sec. is selected, the brake is not
released until the preselected minimum
current is reached.
✮
= Factory setting. Text in ( ) = Display text.
The figures in [ ] are used in bus communication.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com