Packet switches are devices designed to connect electrical contacts, turn them on and off in household low-voltage lines. Nominal operating voltage of alternating current up to 380 V. DC - up to 220 V, working frequency 50, 60 and up to 400 Hz. The device does not belong to highly effective protective devices, but due to its simplicity and affordability it is in wide demand among consumers.
Scope of application
Batch switch can be found:
- In electric boards, consoles, working with low-voltage direct and alternating current.
- In household electrical networks, switching devices with manual transmission for infrequent use.
- For connection / disconnection of engines or individual devices, the operation of which must be monitored by separately derived equipment, including the alarm.
Packet switches can have several working poles (up to 4 pieces). Depending on their number, includes the corresponding number of switching packages that have moving and stationary contacts.
Contacts that are in motion are fixed on an insulated movable pivot pin (one turn is performed through 90 °).
Stationary contacts are shaped like knives and installed in plastic washers.
Batch switch PV looks similar to a small barrel with leads and a handle.
Movable and fixed contacts have fiber washers. The design includes springs that allow switching at the same speed, regardless of the speed of rotation of the handle.
The body is a set of parts, including washers, studs and other small components.
The principle of operation is simple. When the handle is rotated to the required position, the spring is tensioned, and under pressure the spring washer is rotated to the resistant switching state. The cover has clamps that stabilize the position of the washer. When the washer is rotated, the contacts connected to it are activated, which leads to the flow of electricity into the network.
The design feature is uninsulated terminals that are live when the device is connected to the network. Before performing work to prevent accident, the circuit breakers must be disconnected from the network.
Packet switches have fixed contacts that are offset from each other, which allows you to make a convenient connection to them. Terminals are located in different parts of the case, so that the incoming power cables are located on one side of the tightening rods, and in the opposite - wires coming from consumers. Switching on / off occurs when the position of the handle is changed by 90 °.
Switch packet PV 3 16A: work and design features
Standard designation of package switches (cam type in the form of a barrel) PV 3 16 A - “PV - X –UUH HH xxxx xxxx”, in which:
- PV - packet switch;
- X is the number of poles. 3 - three-pole switch;
- UUU - the size of the rated current. 16-16 A;
- HH - climatic modification according to GOST 15150;
- xxxx - the level of protection of the material used for the manufacture of the body.
If there is no sign IP00: kar.IP30 - carbolite body; PL56-IP56 - non-flammable impact resistant plastic is used; sil56-IP56 - material silumin.
xxxx - installation method:
- Fixed front bracket, panel thickness 4mm.
- Fastening with a front bracket, installation behind the panel with a thickness of 25 mm.
- Intra-cabinet mounting for the rear bracket.
- In the absence of designations - installation is carried out directly behind the shell of the device.
Depending on the version, the device has different dimensions and weight.
Advantages and disadvantages
The design of the PV has low wear resistance and is not intended for frequent use. Estimated number of cycles up to 10,000.
The package switch has several advantages:
- Compactness in comparison with powerful and large-sized knife switches.
- When the power is cut off, the circuit is simultaneously broken in two places.
- Contact break and arc quenching occurs almost instantaneously due to the spring mechanism.
- The presence in the design of fiber spark arresters between the movable contacts. The gas released from the fiber, when heated, extinguishes the arc, moving through the slots of the apparatus package.
The dimensions of the packet switch allow installation in any size panel. Despite the outdated design, reliability and quick response make the device popular and in demand today.