The KYN28-12 type distribution cabinet is a type of armored withdrawable metal-clad switchgear, which is a kind of high-voltage switchgear. Because its vacuum circuit breaker is often placed in the middle, it is referred to as a center-mounted cabinet, which is both vivid and easy to remember. The high voltage of the center-mounted cabinet is 3.6/7.2/12kV, in three categories, with 12kV being the most common. The model is KYN28-12 type center-mounted cabinet. The center-mounted cabinet is an indoor high-voltage complete distribution switchgear within a three-phase AC 50Hz single busbar section or double busbar section system.

The structure of the center-mounted cabinet is divided into upper, middle, and lower layers. The upper layer is the busbar compartment and the instrument compartment, with the instrument compartment at the front and the busbar compartment at the back, separated by a partition. The middle layer is the switch compartment, which is the compartment for placing the vacuum circuit breaker. The circuit breaker adopts a drawout-type vacuum circuit breaker, which is easy to install. For maintenance and replacement, the circuit breaker trolley can be pulled out without the need for power interruption. The lower layer is the cable compartment, which has ample space and can connect multiple cables.

It is mainly used in power plants, power transmission for small and medium-sized generators, power distribution for industrial and mining enterprises, and for receiving and transmitting power in secondary substations of the power system, as well as for starting large high-voltage motors. It is used for control, protection, and monitoring. This switchgear meets the requirements of standards such as DL/T40491, IEC298, and GB3906. It has interlocking functions to prevent the drawout of the circuit breaker trolley under load, prevent incorrect opening and closing of the circuit breaker, prevent closing the circuit breaker when the grounding switch is in the closed position, prevent誤入帶電隔室 (accidental entry into live compartments), and prevent誤合接地開關(guān) (incorrect closing of the grounding switch) when live. It can be equipped with either VS1 vacuum circuit breakers or ABB's VD4 vacuum circuit breakers. It is truly a high-performance distribution device.