Electrical Installation; Power Connections - Danfoss VLT HVAC Drive FC 102 Operating Instructions Manual

Electrical Installation

4 Electrical Installation
4.1 Electrical Installation

4.1.1 Power Connections

Cabling and fusing
4 4
NOTICE
Cables in General
All cabling must comply with national and local
regulations on cable cross-sections and ambient
temperature. UL applications require 75 °C copper
conductors. 75 °C and 90 °C copper conductors are
thermally acceptable for the frequency converter to use
in non-UL applications.
The power cable connections are located as shown in
Illustration 4.1. Dimensioning of cable cross-section must
be done in accordance with the current ratings and local
legislation. See chapter 7 General Specifications for details.
If the frequency converter does not have built-in fuses, use
the recommended fuses to protect it. See
chapter 4.1.15 Fuse Specifications for recommended fuses.
Always ensure that proper fusing is made according to
local regulation.
The mains connection is fitted to the mains switch if this
switch is included.
3 Phase
power
input
Illustration 4.1 Power Cable Connections
NOTICE
The motor cable must be screened/armoured. If an
unscreened/unarmoured cable is used, some EMC
requirements are not complied with. To comply with
EMC emission specifications, use a screened/armoured
motor cable. For more information, see EMC specifi-
cations in the product-related design guide.
See chapter 7 General Specifications for correct
dimensioning of motor cable cross-section and length.
36
Operating Instructions
91 (L1)
92 (L2)
93 (L3)
95 PE
Danfoss A/S © 08/2014 All rights reserved.
Screening of cables
Avoid installation with twisted screen ends (pigtails). They
spoil the screening effect at higher frequencies. If it is
necessary to break the screen to install a motor isolator or
motor contactor, continue the screen at the lowest
possible HF impedance.
Connect the motor cable screen to both the decoupling
plate of the frequency converter and to the metal housing
of the motor.
Make the screen connections with the largest possible
surface area (cable clamp). These connections are made by
using the supplied installation devices within the
frequency converter.
Cable length and cross-section
The frequency converter has been EMC-tested with a given
cable length. Keep the motor cable as short as possible to
reduce the noise level and leakage currents.
Switching frequency
When frequency converters are used together with sine-
wave filters to reduce the acoustic noise from a motor, set
the switching frequency according to 14-01 Switching
Frequency.
Term. 96 97 98 99
numb
er
U V W 1) Motor voltage 0–100% of mains
PE
voltage.
3 wires out of motor.
U1 V1 W1 Delta-connected.
1)
PE
W2 U2 V2 6 wires out of motor.
U1 V1 W1 1) Star-connected U2, V2, W2
PE
U2, V2 and W2 to be intercon-
nected separately.
Table 4.1 Motor Terminals
1) Protected Ground Connection
NOTICE
In motors without phase insulation paper or other
insulation reinforcement suitable for operation with
voltage supply (such as a frequency converter), fit a sine-
wave filter on the frequency converter output.
MG11F502