Uses and Types Of Switches In Heavy Commercial Vehicles

Switches, no matter if they are toggle, push button, disconnect, or rockers, are to be seen in every 12v and 24v electrical circuit. These switches for commercial vehicles are used to turn on or off the engine, lights, and moderate electrical systems. We must first understand the circuit inside before moving on to the switches. 

Let’s me give you a brief;

SPST and DPDT

These acronyms stand for Single Pole Single Throw and Double pole Double Throw, poles refer to the number of circuits the switches can control, and throws represent the different positions in which a switch can control a circuit. Therefore, only one electric circuit could be controlled by a single pole switch and a double pole switch can control two circuits acting as two identical switches that are internally linked. In the automotive sector and in truck spare part aftermarket it is very rare to see a switch with more than three poles.

Similarly, single throw switches can connect a circuit at only a single position whereas double pole switches can connect a circuit in an upwards or downwards position as a DT switch also has a center position ( generally configured as on-off-on). Among the two configurations, the most commonly used for truck parts is SPST (single pole single throw) which is largely known as the general on and off switch we use every day. The Double Pole Double Throw switch allows for the use of tandem circuits.  

There are different types of switches in a commercial vehicle. Each type of switch has a different purpose. Generally speaking, switches in an electrical setting are used to ON or let the current pass and OFF or let the current break. This can be illustrated with a simple diagram. 

A Simple switch functions like this. The battery and Switch are attached together using wires to the Positive and negative sources. The switch and electrical component, to which the current has to be given, are connected using wires. When the ON is pressed on the switch, the current through the wires passes from the battery to the electrical component and it is ignited (like LED light, halogen, fog light, etc). When the OFF is pressed on the switch, the current does not pass through to the electrical component

There are two types of switches – mechanical and electronic switches. Mechanical switches require one to press the ON/ OFF button and are operated manually. Electronic switches do not require manual operation and are activated by semi-conductors action. Below is a photo with generic examples of Push buttons, rockers, slides, and magnetic-type switches.

Momentary and Maintained

Another thing about a circuit that should be noticed is how a switch is activated. A momentary switch is the one that is activated only when the user is interacting with it. For example, a push-button ignition switch, window control switch, etc.

 Maintained switches, however, stay in the position the user desires them to be in that moment until flipped back by the user again. For example, light switches, wiper switches, etc. 

Types of common voltage electrical switches:

Rocker switches: These switches have a number of automotive applications, as truck parts they can be used to indicate the on and off status of various components, making them the perfect fit for dashboard functions such as lights and auxiliary applications. 

Toggle Switches: These switches are mostly used as commercial vehicle parts, they can be utilized as truck parts in almost every commercial vehicle. A lever or other mechanism manually activates toggle switches. They can be applied as a battery switch, ambient light switch, Stereo switch, etc. 

Push Button Switches: These switches activate when interacted with by a push. These switches can be utilized as both, electrical spare parts and chassis spare parts as they perform well for exterior lights and door jamb switches. 

Momentary push button switches: These switches are a sub-type truck part of the general push button switches (mentioned above), these switches only activate for as long as the physical pressure is being applied to them by the user. These switches are largely applicable in horns and parts and light dipper functions. 

Ignition Switches: As the name suggests, as a truck part these switches provide reliable circuit control for the truck’s ignition. These switches are designed for universal applications and can be used in almost every type of commercial vehicle. An ignition switch when activated by a lever or key, completes the circuit providing power to the engine and turning the vehicle on and off.