If there are high-voltage switchgear, is an MCC cabinet still needed?
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Are 5 10KV 500KW motors require an MCC cabinet? Under what circumstances is an MCC cabinet needed?
It’s not necessarily required; it depends on the financial situation and the owner’s preferences. MCC motor protectors are generally used for high-end control systems, but we can also use thermal relays in combination with contactors
Let me ask again: according to the drawings, the high-voltage lines enter the plant area first, going into the high-voltage distribution cabinets, and from there they proceed to the high-voltage switchgear, which in turn is connected to the motors. Are switchgear cabinets and distribution cabinets the same thing? I’m sorry, I really don’t understand this
To be precise: it starts with the incoming cable cabinet (high-voltage distribution cabinet), and then through the busbars to the outgoing cable cabinets for motors and transformers, as well as the high-voltage switchgear). They all belong to high-voltage switchgear, but their functions are different
Taking a 10/0.4KV system as an example, the distribution cabinet is equivalent to the cabinets found in a regular power distribution room, while the switchgear is equivalent to the power supply box
Does the motor need to be connected to a host computer? Such as the DCS that has already reached a certain scale. If it’s not necessary, there’s no need to use MCC; using soft start is sufficient
The motor signals can be transmitted to the soft starter cabinet via the PLC; can the soft starter cabinet be used in place of the high-voltage switchgear? The technical team said that the motor uses high-voltage direct start
Motors with a power of 7.5KW or more require electromagnetic starting devices for control (including soft start and frequency conversion). High-voltage motors are usually controlled by high-voltage switchgear, with one switchgear unit typically being able to control only one motor. Alternatively, high-voltage switchgear can be used in combination with frequency converters and soft starter cabinets to achieve more complex functions. An MCC is typically used for the control of low-voltage motors and usually features a modular design; one MCC cabinet contains multiple circuits that enable the control of several motors. It is commonly referred to as a power distribution cabinet.