Baldor MicroFlex e100, Installation Manual

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3-14 Basic Installation MN1942
3.4.3.3 Supplying input power from a variac (variable transformer)
When AC power is supplied from a variac, the MicroFlex
e
100’s pre-charge circuit may not
operate correctly. To ensure that the pre-charge circuitry operates correctly, increase the variac
voltage to the desired level and then power cycle the 24 VDC control circuit supply. This will restart
the pre-charge circuit and allow it to operate correctly.
3.4.4 Power disconnect and protection devices
A power disconnect should be installed between the input power supply and the MicroFlex
e
100
for a fail-safe method to disconnect power. The MicroFlex
e
100 will remain in a powered
condition until all input power is removed from the drive and the internal bus voltage has depleted.
The MicroFlex
e
100 must have a suitable input power protection device installed, preferably a
fuse. Recommended circuit breakers are thermal magnetic devices (1 or 3 phase as required)
with characteristics suitable for heavy inductive loads (C-type trip characteristic). Circuit breaker
or fuses are not supplied - see section 3.4.5. For CE compliance, see Appendix D.
Circuit Breaker
L
N
From
supply
L
N
From
supply
Fuse
L
N
L
N
Figure 4 - Circuit breaker and fuse, single-phase
Circuit Breaker
Circuit breaker or fuse are not supplied.
For CE Compliance, see Appendix C.
L1
From
supply
Fuses
L2
L3
L1
L2
L3
From
supply
L1
L2
L3
Figure 5 - Circuit breaker and fuse, three-phase
Note: Metal conduit or shielded cable should be used. Connect conduits so the use of a
line reactor or RC device does not interrupt EMI/RFI shielding.
3.4.4.1 Using 2 phases of a 3-phase supply
Power may be derived by connecting two phases of an appropriate three-phase supply (L1 and
L2 for example). When supplying AC power in this way, the voltage between the two phases must
not exceed the rated input voltage of the MicroFlex
e
100. A two pole breaker must be used to
isolate both lines. Fuses must be fitted in both lines.