KEB Combivert, Начало работы

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ANTRIEBSTECHNIK
13
2.4 Electrical Connection
Before any installation and connection work, the system must be switched off and
secured. After clearing the frequency inverter the intermediate circuit capacitors
are still charged with high voltage for a short period of time. The unit can be worked
on again, after it has been switched off for 5 minutes.
With frequency inverters that are not isolated from the supply circuit all control lines
must be included in other protective measures (e.g. double insulation or shielded,
earthed and insulated). Further information is found in the technical documentation
part 3.
Connection of the frequency inverter is only permissible on symmetrical networks
with a maximum line voltage (L1, L2, L3) with respect to earth (N/PE) of 300V. An
isolating transformer must be used for supply networks which exceed this value!
The units may be damaged if this is not observed.
The inverter is only designed for a fixed connection, because when using filters
a leakage current > 3.5mA can occur. Protective conductor cross section must be
at least 10mm
2 copper or a 2nd conductor must be electrically parallel to the
protective conductor on separate terminals. Ground point-to-point with the shortest
connection possible to mains earth (avoid earth loops).
When using IGBT inverters, high voltage peaks may arise in the motor due to the
switching action of the inverter output devices. These voltage peaks may damage
the insulation of the motor winding and must be taken into account when using
motor cables longer than 15m with high frequency motors. In this case, the motor
can be protected with a motor choke, dv/dt filter or sine filter.
When doing an insulation measurement in accordance with VDE 0100 / Part 620,
the power semiconductor of the unit and existing radio interferience filters must be
disconnected because of the danger of destruction. This is permissible in
compliance with the standard, since all inverters are given a high voltage test in
the end control at KEB in accordance with EN 50178.
When using components without isolated inputs/outputs, it is necessary that
equipotential bonding exists between the components to be connected (e.g.
through the equalizer). Disregard can cause destruction of the components by the
equalizing currents.
A trouble-free and safe operation of the frequency inverter is only guaranteed when
the connection instructions below are strictly followed. Incorrect operation or
damage may result from incorrect installation.
– Note mains voltage and rated motor voltage.
– Install power cables and control cables separately (> 15cm separation).
– Use shielded/twisted control lines. Connect shield to PE at inverter only.
– Only use suitable circuit elements to control the logic and analog inputs, whose
contacts are rated for extra-low voltages.
– Make sure inverter and motor housing are well grounded. The screen of the
cable between the inverter and the motor must be directly and securely attached
to both the inverter PE terminal and the motor ground terminal. Remove paint
finish where necessary.
– Connect the braking module/ braking resistor with shielded/twisted cables
(install shield on one side of the inverter).
– Ground the cabinet or the system earth star point with the shortest connection
to mains earth (avoid earth loops).
Only Fixed
Connection
Insulation
Measurement
Voltage Peaks
Note Capacitor
Discharge Time
Voltage with
respect to
ground
Prevent
Disturbances
Control
Lines
Different Earth -
Potentials