Batch switch: what is it and what is it for

Batch switches are used for switching electrical circuits. At the same time, they can be used both in direct and alternating current circuits with voltage of 220, 380 V. However, people often confuse and, in the old fashion, call “circuit breakers” circuit breakers, which is fundamentally wrong. Therefore, let's understand what is and what are the need for package switches, as well as how they differ from circuit breakers?

Definition

A packet switch is a switching device for turning on and off electric circuits, actually for the same purposes as circuit breakers. He got this name due to the fact that it consists of the same type of elements (packages) assembled on the same axis and secured with pins. Thus, in production from the same parts you can assemble a switching device with any number of poles (contact groups).

They are characterized by a rotary movement of the control stick and contacts, and not moving along the vertical or horizontal axis, as in toggle switches, knife switches and automatic machines.

The batch switch is controlled manually, that is, it does not disconnect the circuit in case of overload, as the circuit breakers do.

Packets come in different designs and are designed for switching currents of various sizes, both fully domestic 16A and powerful 200A. At the same time, the service life is limited by the design features of the device, so the number of switching cycles lies in the range of 5000-15000 times.

Device

The batch switch consists of a set of insulating plates and contact groups fixed on one axis. The handle is mounted on the upper end of this axis and is rigidly fixed in one of the positions. The switch usually has two positions (“on” and “off”).

Structurally, almost a similar device is a package SWITCHES, as the name implies, they are needed to switch circuits. Usually they have many contact groups (packages), the number can be from several to 10-12 pieces. In the figure below you see package switches and switches with a different number of packages and the general arrangement of modern products.

Batch switches can have more positions than just “on” and “off”, and in each position either contacts are alternately closed, or are closed in any sequence or groups to implement certain switching schemes. An example is shown in the figure below.

At the same time, in the marking of a particular device, its type is indicated (PV - switch, PP - switch), design, installation method, switching scheme, etc. An example of decoding the marking of domestic products (KEAZ) is given below.

Scope of application

Batch switches were actively used in the electrical panels of apartments to turn off or turn on the voltage in the apartment. And still in the old housing stock they are often found. A variant of the connection diagram you see below.

However, at present, instead of them, circuit breakers or load switches (an analogue of knife switches) are used at the input.

They can also act as switches of individual circuits of large electrical installations, for example, for switching power supply of relay protection circuits and other things. But at present, it is difficult to justify the use of batch switches as input switching devices in switchboards.

While the cam packet switches were actively used and will be used, more often not in domestic electrical installations, but in production.With their help, it is convenient to make circuits for switching circuits, ways to control something (local, remote), reversing the engine and switching its windings (different speeds or a star-delta at startup, etc.) and a number of other complex tasks.

The figure above shows an example of using a batch switch to reverse a three-phase asynchronous motor - the contacts in positions 1 and 2 switch so that the phase sequence changes, in position 0 they are all open.