In more recent years high efficiency 12v systems and an entire market have been built for versatile and easy to use 12v accessories, and what these systems offer Australian campers has bought us along a seriously long way.

Now with more companies competing for your dollar than ever before, there’s an absolutely mind-blowing amount of gear on the market to cater to your every 12v desire, so with added complexity of 12v systems, you are more likely to encounter issues in yours and your friends setups, when installing electical compenents and be baffled by words that people who might know what they are talking about mention,  troubleshoot electrical circuits in their 4WD’s cars or even motorcycles you may be a little bit baffled or confused as to the actual meanings of some of the words and phrases that they use.

So we’ve put together a short list of some of the most important keywords you may hear, to help you understand better, how your 12v system works;

VOLTAGE:
An easy way for people to understand electricity is to think of water travelling through a pipe. Voltage is like the pressure of the water travelling within the pipe and determines how much push there is behind the flow. A healthy resting voltage (without help from a charger or alternator) for a 12v battery is more likely around 12.7v or higher. where a dead 12v battery is usually on 12v or less.

AMPS:

Amps (current), when thought of, in the same analogy as used above represent the volume of water travelling through the pipe and therefore the overall “power” that is available to do work. and are what does the

AMP HOURS:

A measurement of how many amps a battery can supply over a period of time. An Adventure Kings 115Ah AGM battery that can safely be drained to 50% has roughly 60 amp-hours (Ah) of capacity. If an Adventure Kings 60L fridge/Freezer draws an average of 1.5 Amp, then that battery can run the fridge for 60/1.5=about 40 hours before it gets down to the estimate of around 50%.

OPEN CIRCUIT:

This is when there is a break in the electrical circuit that stops the power from flowing, such as a blown fuse.

SHORT CIRCUIT:

In 4WD terms, when a cable that supplies power prematurely comes in contact with a short out, which is usually to earth like the body or chassis, this is called a short circuit.

VOLTAGE REGULATOR:
Just like a tap regulates the flow of water, a voltage regulator like the MPPT and PWM found in solar panels prevent voltage from rising too high, whilst adjusting amperage to suit.

DC/DC CHARGER:

Acts similar to a 240v car battery charger that you’d use to charge your batteries in the garage, except it is powered by 12v. Will typically include a voltage isolator to only charge when it senses that your vehicle is running, and often has an in-built solar regulator to allow charging by solar panels. Example would be the CTEK D250SA isolator.

VOLTAGE-SENSING RELAY (VSR):

This is a more basic 12v relay that opens or closes depending on the voltage that is supplied to it. In a dual battery system, this relay works by opening when it senses enough voltage at the designated battery, through this it can tell if the engine is running. A VSR like the on in the Adventure Kings Dual Battery System Kit, allows the auxiliary battery charge off your crank battery. When the vehicle is switched off, the relay closes, isolating the second battery and ensuring your 12V fridge and LED Camping lights don’t drain your crank battery’s power.

SERIES WIRING:

A way of joining two batteries in a daisy chain from positive to negative. This instantly doubles the voltage of the 2 batteries. This setup is typically used in older 24v diesel motors using 2 12v batteries connected in series.

PARALLEL WIRING:

A way of joining two or more batteries positive to positive and negative to negative, adding the batteries amp hour capacities together without changing the overall voltage.

Two Adventure Kings 115Ah 12v batteries connected in parallel essentially form one giant 230Ah 12v battery – which is what you’d want if you wanted to power your fridge or camp lights for a long time.

VOLTAGE DROP:

Voltage drop is a phenomenon, where voltage decreases over the length of a wire due to electrical resistance, this is why the wires that connect directly to your battery are thick and meaty. Thicker wiring prevents voltage from dropping below an acceptable level and in some circumstances can be prevented by placing a DC-DC charger or voltage regulator closer to the battery that requires recharging as the voltage drop from the regulated output is decreased the closer it is to the source.