ABB SafeGear MCC, Инструкция по установке, эксплуатации и обслуживанию

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I N S TA L L AT I O N , O P ER AT I O N A N D M A I N T EN A N C E M A N UA L
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Power cables compartment
The power cables compartment has
provisions for several devices, for
instance: current transformers (up to 3
per phase), surge arresters and ground
sensor.
The power cables compartment has
enough space to lodge up to 2 power
cables per phase of 350 MCM (133%
insulation level) with a stress cone each.
Contactor ground contact
The ground contact is located at the front
of the contactor compartment.
The contactor is grounded in each position.
Secondary connection
Each contactor compartment includes
an automatic device that connects the
contactor low voltage control circuit, as
well as to connect the circuit of opening
and closing of the contactor.
Primary connection
Consists of a set of three copper contact
fingers compressed by springs, these can
be inspected by removing the contactor
from the compartment. Line side finger
contacts apply the correct pressure over
the terminals, achieving self-alignment
of the devices. All copper parts are
silverplated (tin plated are an option) for
better conduction.
Bus bars and supports
Bus bars are electrolytic copper sheathed in heat epoxy hysol (coating shrinkable
tubing as an option). They run horizontally and vertically along the bus and cable
compartments. The cross section allows meeting the current specified by the design.
The bus supports are polyester GPO-3, this design supports the electrodynamic forces
caused by short circuit effects.
Fig. 6 Contactor compartment
Fig. 9 Controller ground contact
Fig. 7 Power cables compartment Fig. 8 Bus supports and bus bars
Fig. 10 Automatic secondary Fig. 11 Finger contacts