Ac Mains Connection; Mains Connection; External Fan Supply - Danfoss VLT FC 102 Operating Instructions Manual

Electrical Installation
Although failure due to bearing currents is infrequent, use
the following strategies to reduce the likelihood:
•
Use an insulated bearing.
•
Apply rigorous installation procedures.
•
Ensure that the motor and load motor are
aligned.
•
4 4
Strictly follow the EMC Installation guideline.
•
Reinforce the PE so the high frequency
impedance is lower in the PE than the input
power leads.
•
Provide a good high frequency connection
between the motor and the frequency converter.
•
Ensure that the impedance from frequency
converter to building ground is lower than the
grounding impedance of the machine. Make a
direct ground connection between the motor and
load motor.
•
Apply conductive lubrication.
•
Try to ensure that the line voltage is balanced to
ground.
•
Use an insulated bearing as recommended by the
motor manufacturer.
NOTICE
Motors from reputable manufacturers typically have
insulated bearings as standard in motors of this size.
If found to be necessary, and after consultation with
Danfoss:
•
Lower the IGBT switching frequency.
•
Modify the inverter waveform, 60° AVM vs.
SFAVM.
•
Install a shaft grounding system or use an
isolating coupling between motor and load.
•
Use minimum speed settings if possible.
•
Use a dU/dt or sine-wave filter.
40
®
VLT HVAC Drive FC 102 Low Harmonic Drive

4.7 AC Mains Connection

4.7.1 Mains Connection

Connect mains to terminals 91, 92, and 93 on the far left
of the unit. Ground is connected to the terminal on the
right of terminal 93.
Terminal
number
91, 92, 93
94
Table 4.5 Terminal Functions
Ensure that the power supply can supply the necessary
current to the frequency converter.
If the unit is without built-in fuses, ensure that the
appropriate fuses have the correct current rating.

4.7.2 External Fan Supply

Applicable for E and F enclosures only. If the frequency
converter is supplied by DC or the fan must run
independently of the supply, use an external supply. Make
the connection on the power card.
Terminal
number
100, 101
102, 103
Table 4.6 Terminal Functions
The connector on the power card provides the connection
of line voltage for the cooling fans. The fans are connected
from the factory to be supplied from a common AC line
(jumpers between 100–102 and 101–103). If external
supply is needed, remove the jumpers and connect the
supply to terminals 100 and 101. Protect with a 5 A fuse.
In UL applications, use a LittelFuse KLK-5 or equivalent.
Danfoss A/S © 04/2015 All rights reserved.
Function
Mains R/L1, S/L2, T/L3
Ground
Function
Auxiliary supply S, T
Internal supply S, T
MG16I302