Danfoss VLT 6000 HVAC Profibus, Руководство пользователя

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VLT
®
6000 HVAC
159
MG.60.B1.02 - VLT is a registered Danfoss trade mark
All about
VL
T 6000 HV
AC
If very small motors are used without phase coil
insulation, it is recommended to fit a LC filter after the
frequency converter.
Typical values for the rise time and peak voltage U
PEAK
measured on the motor terminals between two
phases:
VLT 6002-6006 200 V, VLT 6002-6011 400 V
Cable Mains Peak
length voltage Rise time voltage
50 metres 380 V 0.3
µ
sec. 850 V
50 metres 460 V 0.4
µ
sec. 950 V
150 metres 380 V 1.2
µ
sec. 1000 V
150 metres 460 V 1.3
µ
sec. 1300 V
VLT 6008-6027 200 V, VLT 6016-6062 400 V
Cable Mains Peak
length voltage Rise time voltage
50 metres 380 V 0.1
µ
sec. 900 V
150 metres 380 V 0.2
µ
sec. 1000 V
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Switching on the input
Switching on the input depends on the mains voltage
in question.
The table below states the waiting time between cut-
ins.
Mains voltage 380 V 415 V 460 V
Waiting time 74 s 95 s 123 s
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Peak voltage on motor
When a transistor in the inverter is opened, the
voltage across the motor increases by a dV/dt ratio
that depends on:
- the motor cable (type, cross-section, length
screened/armoured or unscreened/unarmoured)
- inductance
The natural induction causes an overshot U
PEAK
in the
motor voltage before it stabilises itself at a level which
depends on the voltage in the intermediate circuit.
The rise time and the peak voltage U
PEAK
affect the
service life of the motor. If the peak voltage is too
high, motors without phase coil insulation are the
ones that will primarily be affected. If the motor cable
is short (a few metres), the rise time and peak voltage
are lower.
If the motor cable is long (100 m), the rise time and
peak voltage will increase.
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Acoustic noise
The acoustic interference from the frequency conver-
ter comes from two sources:
1. DC intermediate circuit coils
2. Integral fan.
Below are the typical values measured at a distance
of 1 m from the unit at full load:
VLT 6002-6006 200 V, VLT 6002-6011 400 V
IP 20 units: 50 dB(A)
VLT 6008-6027 200 V, VLT 6016-6062 400 V
IP 20 units: 61 dB(A)
IP 54 units: 66 dB(A)