Baldor Flex+DriveII, Руководство по установке

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Basic Installation 3-11 MN1902
3.4.3 Input power conditioning
Baldor drives are designed for direct connection to standard single and three-phase lines
(depending on model) that are electrically symmetrical with respect to earth/ground. Certain
power line conditions must be avoided; an AC line reactor, an isolation transformer or a step
up/step down transformer may be required for some power conditions:
H
If the feeder or branch circuit that provides power to the FlexDrive
II
has permanently
connected power factor correction capacitors, an input AC line reactor or an isolation
transformer must be connected between the power factor correction capacitors and the
FlexDrive
II
.
H
If the feeder or branch circuit that provides power to the FlexDrive
II
has power factor
correction capacitors that are switched on line and off line, the capacitors must not be
switched while the drive is connected to the AC power line. If the capacitors are switched
on line while the drive is still connected to the AC power line, additional protection is
required. A Transient Voltage Surge Suppressor (TVSS) of the proper rating must be
installed between the AC line reactor (or isolation transformer) and the AC input to the
FlexDrive
II .
3.4.3.1 Input power-cycling
If AC power has been removed from the FlexDrive
II
, it should not be reapplied for at least one
minute. This delay allows the input surge protection circuit to perform correctly. Power-cycling
the drive more frequently could cause nuisance trips when power is reapplied and reduce the
lifetime of the FlexDrive
II .
3.4.4 Power disconnect and protection devices
A power disconnect should be installed between the input power service and the FlexDrive
II
for a fail-safe method to disconnect power. The FlexDrive
II
will remain in a powered condition
until all input power is removed from the drive and the internal bus voltage has depleted.
The FlexDrive
II
must have a suitable input power protection device installed. Recommended
circuit breakers are thermal magnetic devices (1 or 3 phase as required) with characteristics
suitable for heavy inductive loads (D-type trip characteristic). Recommended time delay fuses
are Buss FRN on 230VAC or equivalent, following the UL 508C recommendation of a fuse
size of four times the continuous output current of the drive. Dual element, time delay fuses
should be used to avoid nuisance trips due to inrush current when power is first applied.
Circuit Breaker
L
N
From
supply
L
N
From
supply
Fuse
L
N
L
N
Figure 4 - Circuit breaker and fuse, single-phase (package sizes A, B, C, D)