Zener MSC-3, Instruction Manual

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IM00120 9 IM00120
MSC-3 Instruction Manual
MSC-3 Power wiring for 3 Phase supply
Basic power wiring diagram
L1 L2 L3
L1 L3 L2 M1 M3 M2 E
3 Phase Supply
MSC-3
SD08298A
MOTOR
CAUTION
Be sure to review the
information on the following
pages concerning electrical
installation issues.
See installation practices for
Electromagnetic compatibility
(EMC) compliance on
page 13 and specific
information for the EMC
compliant installation of each
chassis size on pages 14
- 18 BEFORE selecting or
installing motor cables and
glands.
The screened motor cable
should only contain the phase
and earth (PE) conductors
of one inverter and the
associated motor. Do not
include other conductors
inside the screen.
Supply circuit protection and switchgear
Either fuses or a circuit breaker must be connected as shown. The protective elements used and any
upstream switchgear (contactors, isolation switches etc) must be selected with due regard for the
prospective short circuit currents of the electrical supply and the requirements of your local electrical
code. The selection should provide for “type II” (no damage) coordination as per IEC 60947 or Australian
Standard AS 3947.
Fuses or circuit breakers of the current limiting type are preferred in order to minimise the total energy let
through in the unlikely, but possible, event of a major arcing fault in wiring or within MSC-3 enclosure.
Installations that are required to be UL compliant must use UL listed fuses of the amp rating and class
detailed on page 10 of this manual.
Cable sizes
Cable sizes should be selected according to local wiring rules using the currents given in the table on
page 10. Note that the power terminals of the MSC-3 are designed to accept normally stranded
power cables with temperature rating of 70ºC or more. In the event that other cable types are to be used
(particularly flexible cables with very fine stranding), the overall size of the conductor should be checked
prior to final cable selection for proper fit in the power terminals. The combination of the cable and the
supply circuit protection selected must be such that the supply cable is properly protected under all
circumstances.
Electrical Isolation
A suitable means of isolating the MSC-3 from the electrical supply must be provided in accordance
with your local electrical code. In the event that a second supply is connected to the relay contacts on
the control terminal strip (or otherwise brought into the MSC-3 enclosure), suitable marking must be
applied to the outside of the MSC-3 enclosure by the installer to indicate the dual supply arrangement
in accordance with your local electrical code and other safety requirements. A means of isolating the
second electrical supply source will also be required.