Forklift Drive Motors - Motor Control Centers or MCC's, are an assembly of one or more enclosed sections, which have a common power bus principally comprising motor control units. They have been used since the 1950's by the vehicle business, in view of the fact that they used a large number of electric motors. Now, they are utilized in a variety of industrial and commercial applications.
In factory assembly for motor starter; motor control centers are fairly common method. The MCC's include metering, variable frequency drives and programmable controllers. The MCC's are commonly seen in the electrical service entrance for a building. Motor control centers frequently are used for low voltage, 3-phase alternating current motors that range from 230 volts to 600 volts. Medium voltage motor control centers are designed for large motors that range from 2300V to 15000 V. These units make use of vacuum contractors for switching with separate compartments in order to achieve power control and switching.
In places where extremely corrosive or dusty methods are taking place, the motor control center may be installed in a separate air-conditioned room. Usually the MCC would be positioned on the factory floor near the equipment it is controlling.
For plug-in mounting of individual motor controls, A motor control center has one or more vertical metal cabinet sections with power bus. In order to complete testing or maintenance, very large controllers can be bolted into place, while smaller controllers could be unplugged from the cabinet. Every motor controller consists of a solid state motor controller or a contractor, overload relays to protect the motor, fuses or circuit breakers to provide short-circuit protection as well as a disconnecting switch to be able to isolate the motor circuit. Separate connectors enable 3-phase power to enter the controller. The motor is wired to terminals situated in the controller. Motor control centers supply wire ways for field control and power cables.
Inside a motor control center, each and every motor controller can be specified with lots of different alternatives. Some of the choices comprise: extra control terminal blocks, control switches, pilot lamps, separate control transformers, and various kinds of solid-state and bi-metal overload protection relays. They even have different classes of types of power fuses and circuit breakers.
Concerning the delivery of motor control centers, there are several options for the client. These can be delivered as an engineered assembly with a programmable controller together with internal control or with interlocking wiring to a central control terminal panel board. Conversely, they could be provided set for the customer to connect all field wiring.
MCC's generally sit on floors that are required to have a fire-resistance rating. Fire stops can be necessary for cables which penetrate fire-rated floors and walls.
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