Powering computers in an automotive application isn’t as simple as just plugging it into your 12V DC socket in the vehicle. The power output of a 12V DC socket in a vehicle fluctuates due to the ignition state of the car and this can lead to issues with powering a computer.
Generally, selecting a PSU with a wide input, ranging from 8-32V, will accommodate most vehicle classes and power states of the vehicle allowing the computer to function properly, even with the wide voltage fluctuations. The problem with just simply plugging the computer directly into the 12V DC socket in a vehicle, and running it in dumb mode, is that the 12V DC sockets are directly linked to the state of the ignition, meaning that as soon as you turn your vehicle off the power to the sockets is also turned off. If you are running a computer from the 12V DC sockets and don’t manually turn it off and wait for it to shut down fully before switching off the vehicle, the computer will encounter a hard shutdown. Over time this can lead to OS corruption.
What really sets automotive power supplies apart from regular PSU’s is their ability to integrate into the vehicle’s electrical systems, rather than just plugging it into a 12V socket. The first advantage comes when turning on your vehicle. An automotive power supply unit comes equipped with a wire specifically for integrating the PSU into the ignition circuit of the vehicle. This allows the computer to be switched on automatically at the time of starting up the vehicle, which stops the need for you to turn on your vehicle and then manually switch on your computer. When it comes to turning off your vehicle, if you are using a computer powered by the 12V DC socket and a regular PSU, you have to make sure to properly shutdown the computer before turning the car off. Automotive PSU’s can be wired to the car battery allowing the computer to source power even after the ignition has been turned off.
In industrial applications, such as in a police car, there is a need for the computers to stay on after the vehicle has been parked and turned off, allowing it to transfer the data it has collected during the day to the main system such as within the police station. The advantage of running the computer directly off the battery with the timer settings is that you can switch off your vehicle and the computer can keep running even though the ignition is turned off and all power to the 12V sockets has been cut. This gives the computer time to transfer data and the timer settings can be configured to shut it down safely after a specific period of time. Without running the computer directly off the battery with timer settings the user would, at least, have to leave the accessory power running while the data transfers and then go back and turn it off. Automotive PSU’s also have the ability to monitor the battery charge level ensuring that the draw from the system does not completely drain the battery. These features significantly reduce the energy consumption of the vehicle over time and help maintain an efficient workflow.