Rotary switch is a kind of switch that controls the on-off of the main contact point by rotating the handle. There are also two structural forms of rotary switch, namely unipolar unit structure and multipole multi bit structure. Unipolar unit rotary switch is often used together with rotary shaft potentiometer in application, while multipole multi position rotary switch is mostly used for switching lines in working state.

Rotary switch

The rotary switch can be used to replace the rotary pulse generator with the analog function of the traditional resistance potentiometer. Rotary selector switch are usually used in the man-machine interface of the front panel of the instrument and the audio-visual control board. The Electronic Dimmer Rotary Switch adopts the orthogonal optical encoder as the pure digital device to replace the analog potentiometer. These rotary switches are similar to the traditional or resistance potentiometer in appearance, However, the internal structure of these rotary switches is completely digitized and optical technology is used. Similar to the traditional incremental encoder products, there are two orthogonal output signals (channel A and channel B), which can be directly connected with the encoder processing chip.

Working principle editing and broadcasting

In a certain range, the resistance value is changed, and then there is a Marine Rotary Switches , which is the switch of old-fashioned TV and radio. In the case of fan, there are several gears, which are connected to several groups of outgoing lines of fan winding, and the speed is changed by changing the number of wire circles. The principle is similar to that of potentiometer.and spring return rotary switch.

Structural characteristics of precision rotary switches

The common band switch and the shift switch of the multimeter are rotary switches, which have two structures: one is BBM (break before make) contact type, which is characterized in that when shifting, the moving contact first disconnects the front contact and then connects the rear contact, in which there is a state disconnected from both the front and rear contacts: the other is MBB (make before break) contact type, It is characterized in that during transposition, the moving contact has a state of contact with both front and rear contacts, and then disconnect the front contact to maintain contact with the rear contact. In the circuit design, the appropriate rotary switch shall be selected according to the purpose and safety of the circuit.

Common types of editing and broadcasting

Because of its purpose, the rotary switch adopts a sealed structure as a whole, which has a certain waterproof effect and can basically reach the waterproof level of IP65.

At the same time, it is necessary to use relatively hard and durable metal materials, with the difference of gear 2 or gear 3. Such as FBelec, China brand rotary switch manufacturers:
Electrical Ratings 1A @ 24VDC； 1A @ 125VAC； 0.5A@ 250VAC
Dielectric Strength 2000Vrms min contact to contact
Insulation Resistance ≥ 100MΩ min
Operating Temperature -25ºC to 55ºC
Sealing Degree IP65 standard
Storage Temperature -25ºC to 55ºC
Electrical Life 50,000 cycles typical
Contact Resistance ≤50mΩ initial