12 Volt Frequently Asked Questions (FAQs)

In this section are answers to many of the commonly asked technical questions related to 12 volt wiring. Use this as a quick reference to save you time when deciding what parts to select for your project..........Read more

Electrical Circuit Basics

Electricity is a fundamental part of the workings of most vehicles and this section aims to explain the basic principles. Hopefully this will give you an understanding and allow you to carry out some simple calculations for specifying the electrics in your auto or marine wiring projects.........Read more

Cable Sizing & Selection

One of the most important aspects of any wiring project is determining the correct size and type of cable to use for each circuit. Too small a cable size and you'll run the risk of generating heat in the cable; too large and you'll be wasting money on copper you don't need......Read more

Fusing Guide

Fuses are critical in any electrical system and are used to protect a circuit from excessive current that could lead to damage and, very often, an electrical fire. Excessive current is most likely to be caused by three things........Read more

Relay Guide

Relays are used extensively throughout all modern vehicle electrical systems. They are quite simple devices but very useful, so once you understand how they work and what they enable you to do it opens up a vast range of applications for your aftermarket projects.......Read more

Split Charging Guide

If you own a motorhome, campervan or boat then you'll probably need a 2nd battery to run all of your leisure electrics such as lights, coolbox/fridge, TV, navigation equipment, power sockets etc. In order to keep this 2nd battery charged you'll need to connect it to a power source such as your engine's alternator or a mains battery charger. This is what split charging is all about.......Read more

Auxiliary Battery Charging In Vehicles With 'Smart' Alternators

One of the emissions-reducing technologies that is now becoming standard on new vehicles, is  the 'smart' or 'intelligent' ECU-controlled alternator. Unfortunately traditional split charging systems using VSRs are not compatible with smart alternators so a battery-to-battery charger must be used instead.......Read more

LED Lighting Brightness Guide

Conventional lighting based upon incandescent filament bulbs is traditionally referred to as having an output in Watts. This allows us to have a good understanding of how bright it will be as there is an approximate correlation between power consumed by the bulb (Watts) and brightness.  The problem with LEDs is that they use much, much less power than conventional bulbs for an equivalent light output, so using Watts as a measure of comparing brightness is no longer useful.......Read more