VLT
®
4000 VT
All about VLT 4000
VT
■
Derating for running at low speed
When a centrifugal pump or a fan is controlled by
a VLT 4000 VT AFD, it is not necessary to reduce
the output current at low speed because the
load characterstic of the centrifugal pumps/fans,
automatically ensures the necessary reduction.
■
Derating for long motor cables or cables
with larger cross-section
VLT 4000 VT has been tested using 1000 feet
unshielded/unarmoured cable and 4950 feet
shielded/armored cable.
VLT 4000 VT has been designed to work using
a motor cable with a rated cross-section. If a
cable with a larger cross-section is to be used, it is
recom-mended to reduce the output current by 5%
for every step the cross-section is increased.
(Increased cable cross-section leads to increased
capacity to ground, and thus an increased
ground leakage current).
■
Derating for high switching frequency
A higher switching frequency (to be set in parameter
407
Switching frequency)
leads to higher losses
in the electronics of the VLT AFD.
VLT 4000 VT has a pulse pattern in which it is possible
to set the switching frequency from 3.0- 10.0/14.0 kHz.
The VLT AFD will automatically derate the
rated output current I
VLT,N
, when the switching
frequency exceeds 4.5 kHz.
In both cases, the reduction is carried out
linearly, down to 60% of I
VLT,N
.
The table gives the min., max. and factory-set
switching frequencies for VLT 4000 VT units.
Switching frequency [kHz]
Min.
Max.
Fact.
VLT 4006-4032, 200 V
3.0
14.0
4.5
VLT 4042-4062, 200 V
3.0
4.5
4.5
VLT 4006-4011, 460 V
3.0
10.0
4.5
VLT 4016-4062, 460 V
3.0
14.0
4.5
VLT 4072-4352, 460 V
3.0
4.5
4.5
VLT 4452-4652, 460 V
1.5
3.0
3.0
VLT 4006-4011, 600 V
4.5
7.0
4.5
VLT 4016-4032, 600 V
3.0
14.0
4.5
VLT 4042-4062, 600 V
3.0
10.0
4.5
VLT 4072, 600 V
3.0
4.5
4.5
VLT 4102-4352, 600 V
1.5
2.0
2.0
VLT 4402, 600 V
1.5
1.5
1.5
■
Motor thermal protection
The motor temperature is calculated on the basis
of motor current, output frequency and time. See
parameter 117,
Motor thermal protection.
■
Vibration and shock
VLT 4000 VT has been tested according to a procedure
based on the following standards:
IEC 68-2-6:
Vibration (sinusoidal) - 1970
IEC 68-2-34:
Random vibration broad-band
- general requirements
IEC 68-2-35:
Random vibration broad-band
- high reproducibility
IEC 68-2-36:
Random vibration broad-band
- medium reproducibility
VLT 4000 VT complies with requirements that
correspond to conditions when the unit is mounted
on the walls and floors of production premises, as
well as in panels bolted to walls or floors.
■
Air humidity
VLT 4000 VT has been designed to meet the
IEC 68-2-3 standard, EN 50178 pkt. 9.4.2.2/DIN
40040, class E, at 40°C.
See specifications under
General technical data.
MG.40.A7.22 - VLT is a registered Danfoss trademark
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