60
Restarting after an emergency stop
After an emergency stop, the emergency stop button must be released and a reset
performed before the main contactor (or air circuit breaker and stator contactor) can
be closed and the converter started.
Selecting the power cables
This section contains the general cable selection rules. For a list of recommended
cables, see chapter
Note: The converter configuration may require multiple cabling. See section
side connection procedure
General rules
Dimension the cables according to local regulations:
• The cable must be able to carry the converter load current. See chapter
data
• The cable must be rated for at least 70
temperature of conductor in continuous use.
• The cable must withstand the short circuit current given in chapter
• The inductance and impedance of the PE conductor/cable (grounding wire) must
be rated according to permissible touch voltage appearing under fault conditions
(so that the fault point voltage will not rise excessively when a ground fault
occurs).
• 600 VAC cable is accepted for up to 500 VAC. For 690 VAC rated equipment, the
rated voltage between the conductors of the cable should be minimum 1 kV.
The rated voltage of the supply line cables should be U
rated equipment. (U
voltage between the conductors.)
A four conductor system is allowed for input cabling, but shielded symmetrical cable
is recommended. To operate as a protective conductor, the shield conductivity must
be at least 50% of the conductivity of the phase lead. Compared to a four conductor
system, the use of symmetrical shielded cable reduces electromagnetic emission of
the whole converter system as well as generator bearing currents and wear. The
rotor cable and its PE pigtail should be kept as short as possible in order to reduce
electromagnetic emission as well as capacitive current.
Power cable busbars
If necessary, the same screw can be used for connecting two cable lugs (on both
sides of the busbar). Cable lugs with one or two holes can be used. Always use a
torque wrench for tightening the busbar connections.
Alternative power cable types
Power cable types that can be used with the converter are represented below.
Planning the electrical installation
Technical
in chapter
for the rated currents.
= rated voltage between the conductor and the earth, U = rated
o
data.
Electrical installation.
°
°
C (140
F) maximum permissible
Technical
Technical
/U = 0.6/1 kV for 690 VAC
o
Stator
data.