Dc Supply Connections; Ground Connections - KEB Combivert F5 series Instruction Manual

General

1.5.8 DC Supply Connections

When connecting the F4 series inverter from a DC supply or when connecting several
F4 series inverters to a common DC bus the following points should be observed.
Each inverter must be fused on both the + and - conductors. BUSSMANN DC fuse type
FWP are recommended. The DC input current of the inverter can be calculated using
the equations below.
Connect the positive wire to the ++ terminal and the negative wire to the -- terminal.
Terminals marked PA, PB, or - are not suited for DC voltage input. See page 24 for wiring
example. All previously stated wiring conditions are still valid.
The peak DC supply current can be calculated with the following formulas:
If the motor power factor (PF) is not known, use the value 0.78 as a default.
For additional information about DC supply of the inverter contact KEBCO Inc.

1.5.9 Ground Connections

When working with high frequencies ( > 1kHz ) and power semiconductors it is
recommended to make all ground connections with large exposed metal surfaces in
order to minimize the ground resistance.
The metal sub-plate the inverter is mounted on is regarded as the central ground point
for the machine or the equipment. For best results use an unpainted, galvanized or plated
sub-panel.
The AC motor control or servo system is designed for fixed installation. High
frequency discharge currents in the ground circuit can exceed 3.5mA especially
when using EMI filters. Therefore, an additional high frequency ground wire
should be connected between the inverter and the sub-panel. Use a stranded wire
(6 gauge) or a thick ground strap. This is in addition to the ground wire required
by NEC.
All ground connections should be kept as short as possible and as close as possible to
the ground system, sub-panels.
If other components in the system exhibit problems due to high frequency disturbances,
connect an additional high frequency ground wire between them and the sub-panel.
The KEBCO EMI filter should be mounted to the inverter or as close as possible to the
inverter and on the same sub-panel as the inverter. Good metallic surface contact to the
sub-panel is required to provide adequate high frequency grounding of the filter.
12
230V Supply
2.6 x rated motor voltage x rated motor current x motor PF
460V Supply
2.6 x rated motor voltage x rated motor current x motor PF
310V
620V