En interruptores electrónicos, “Sp” representa “Un solo poste,” “DP” representa “Pole doble,” “CALLE” representa “Lanzamiento,” y “Dt” representa “Doble lanzamiento”; esencialmente describiendo cuántos circuitos independientes puede controlar un interruptor (“polo”) y cuántas posiciones puede cambiar entre (“tirar”) dentro de un solo mecanismo de interruptor.
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Explanation:
Un solo poste (Sp): A switch with only one circuit that can be controlled by the switch action.
Pole doble (DP): A switch that can control two separate circuits simultaneously.
Lanzamiento (CALLE): A switch with only one position, meaning it can either be “on” or “off”.
Doble lanzamiento (Dt): A switch with two positions, allowing it to switch between two different circuits.
Common Switch Combinations:
SPST (Single Pole Single Throw): A basic on/off switch, controlling one circuit with only one position.
SPDT (Single Pole Double Throw): A switch that can connect a single input to either of two different outputs.
DPST (Double Pole Single Throw): A switch that turns two separate circuits on or off together.
DPDT (Double Pole Double Throw): A switch that can independently switch between two different circuits on each of its two poles.

SPDT, DPDT, & 3PDT Switches Differences & Uses
When customers ask us about electronic switches such as button switches and rocker switches. We often ask customers whether they want SPST, SPDT, DPST, DPDT or 3PST, 3PDT. This involves the concepts of extreme numbers and throwing.
SP and DP refer to single pole and double pole respectively, ST and DT refer to single throw and double throw respectively.
The number of poles refers to the number of circuits controlled by the switch: an SP switch only controls one circuit. A DP switch controls two independent circuits (like two identical switches mechanically connected). Don’t confuse “pole” with “terminal”. Por ejemplo, a DPST switch has four terminals, but it is a DP, not a 4P switch.
Throw refers to the extreme position of the actuator: the ST switch closes the circuit in only one position. Another position for the handle is closed. The DT switch closes the circuit in the Up position and Down position (On-On). DT switches can also have a center position (usually On-Off-On).

What are Poles and Throws – SPST, SPDT, DPST, DPDT Switches
Single pole/throw and double pole/throw switches are by far the most common switches, but triple and quadruple configurations are also available. They are usually represented as 3PST, 3PDT, 4PDT, etc..
Functional differences of SP, DP, CALLE, and DT
En interruptores electrónicos, Sp, DP, CALLE, and DT refer to the number of circuits and positions a switch can control:
Sp: Single pole, which means the switch controls one electrical circuit
DP: Double pole, which means the switch controls two electrical circuits
CALLE: Single throw, which means the switch has two positions, such as on and off
Dt: Double throw, which means the switch has three positions, such as on, off, and on
The most common types of switches are:
SPST: Single pole single throw, which has two terminals and is ideal for on-off applications
SPDT: Single pole double throw, which has three terminals
DPST: Double pole single throw, which has four terminals
DPDT: Double pole double throw, which has six terminals
A switch’s poles and throws define its internal circuit structure and contact form.

How to Choose an Electrical Switch
SP and DP refer to single pole and double pole, ST and DT refer to single throw and double throw.
The number of poles refers to the number of circuits the switch controls: SP switches control only one circuit. DP switches control two separate circuits (and act like two identical switches mechanically connected). Don’t confuse “poles” with “terminals.” Por ejemplo, a DPST switch has four terminals, but it’s a DP, not a 4P switch.
The throws refer to the extreme positions of the actuator: ST switches close the circuit in only one position. The other position of the handle is Off. DT switches close the circuit in the Up position and the Down position (On-On). DT switches can also have a center position (usually On-Off-On).
SP/Throw and DP/Throw switches are by far the most common switches, but triple and quadruple configurations are also available. They are often denoted as 3PST, 3PDT, 4PDT, etc..