ELLEN Dewar’s FJ Cruiser has been steadily modified to suit her often nomadic role as both 4X4 Australia snapper and keen off-road tourer. As you’d expect, Ellen is often away from ‘regular’ power sources when on assignment, so when it comes to recharging camera batteries, working on laptops and powering some of the other accessories fitted to her rig, a battery charging system was a must-fit.


MODERN 4x4s are complex, especially when it comes to power which, these days, sees vehicle alternators often controlled by the ECU, making hooking up an auxiliary battery a more involved process than it was in the past. Enter the Redarc BCDC1225D charger, a multi-stage charger designed specifically to cater for that complexity, as Phil Cochrane from Ontrack Automotive ( explains.

“If the vehicle is equipped with a voltage sensitive alternator – which is computer (ECU) controlled – that’s the charger we’ve got to use most of the time now, otherwise it won’t fully charge second batteries,” he says. “If the alternator is controlled by the ECU … some of these Ford Rangers, they turn the alternator off while they are travelling and then turn it back on once the voltage drops below certain volts to recharge it. And then the alternator is switched back off again – it’s an absolute nightmare.”

This also means the second battery can often never reach full charge, so fitment of the charger is a way to ensure the auxiliary power source is always juiced up, ready to go. This is different to older vehicles, where fitment of a solenoid-based management system is still effective.

“If the vehicle is charging at over 14 volts then we’ll put a solenoid on them, but if they’re charging under 14 we won’t do that,” Phil explains. “I reckon a solenoid is more reliable, but some people don’t like the solenoids anymore. It’s what the customer wants basically, so we do it this way if that’s their preference.”


FOR the FJ Cruiser, Phil chose a charging system that reflects Ellen’s needs. Often out in remote areas, being able to keep cameras and laptops charged, as well as food and drinks cold, is an essential for her, so the Redarc BCDC1225D is ideal.

“The system we fitted to Ellen’s vehicle was a charging system, so it works off the vehicle’s engine management system to charge the battery,” Phil explains. “As a charging system, it doesn’t actually work off the alternator. So what it does, it charges as a multi-stage charger; it will charge for a certain percentage and then it will ‘float’ and ‘boost’ when the battery needs the correct amount of power.”

When Phil is talking about power ‘floating’ he is describing how the charger stores excess charge; if the battery is full and cannot take any more charge, then the BCDC1225D ‘floats’ (or stores) that excess and will just trickle power into the battery (down to 0.5amp) until it needs more of a boost. Then, that excess charge is utilised. This self-regulation ensures full capacity at all times.

Impressively, the BCDC1225D is more than a one-trick pony – the ‘D’ signifies solar power capability, and a capability that is super simple and very effective.

“It [the Redarc BCDC1225D] is a charging system that can also operate off a solar panel, so it’s got the input on the charger,” explains Phil. “So, if you wanted to plug a solar panel into it, you can, and without using a solar regulator.

“The charger does all the regulating to the battery, so, as long as the charger is getting over 18 volts to it from the solar panel, it automatically converts it to 14.3V to the battery. It’s a fantastic system the way it works, compared to just a solar panel with a built-in regulator that can only put in a maximum of 8amp (this depends to a degree on the size of the solar panel).

“With this system, if the battery charger is getting about 21 volts from the solar panel it will put in the 25amp, so they are a very good system – they work fantastically.”

Having the ability to gain maximum input from the solar panel, and all through a direct connect to the charger, makes for a hassle-free recharging process when you’re in the middle of nowhere.

When quizzed on the amount of grunt needed to power an off-road vehicle’s accessories – fridge/freezer, lights, winch, etc. – Phil reckons that, generally, this model charger (at 25amp) is more than enough.

“Most people run a fridge, some lights and everything else, so during the day when you’re driving, the charger will charge the battery back up to its full capacity,” he reckons. “At night time the battery will use what it’s got to use to keep the appliances charged, so, by doing that, most of the time, a single battery only requires a 25amp charger.”

However, he does suggest for those running two fridges, a pile of power-based accessories or two auxiliary batteries, the 40amp model is the one to go for.



THE fitment of the Redarc system to Ellen’s FJ is a day-long gig, with auxiliary battery choice and protection fuse location just some of the things to factor in when fitting. Phil used a fullysealed lead-acid Century battery as the auxiliary battery choice as it is more heat-resistant, and being mounted underbonnet means it will be subject to plenty of high temps. He also tries to get the biggest capacity battery he can into the space allocated – in this case, an 82A/h jobbie.

Pre-fitment, Phil went over the vehicle with Ellen to discuss what she wanted and where she wished the power outlets/points to be located, and also what types were required. For this particular FJ Cruiser, it was two in the back – a Merit socket and 12V socket – plus an Anderson plug for the fridge/freezer.


To ensure power spikes don’t affect the two connected batteries, protection fuses are fitted between them, with Phil opting for 40amp midi-fuses, which have to be fitted in certain locations for optimum protective performance.

“If it’s a 25amp charger, we put a 40amp midi-fuse in there; if it’s a 40, we up the fuse size to a 60amp,” he says. “We use the midi-fuses as they are the best on the market, as they can take the current and high flow.”

He does mention the fact any charger can be affected by nearby heat and can shut down if over-heated; they work best in a (relatively) cool environment, with a location like the back of an engine bay as one example of where they can be positioned for optimum performance.





THE FJ Cruiser is a common vehicle through the Ontrack Automotive workshop, and this gave Phil the chance to show Ellen previous examples of the Redarc system. Surprisingly (or not?) the team there made up specialty brackets for the many LC79s that come in, and these also fit the FJ Cruiser perfectly. Phil also mentions his LC79 as proof of the Redarc system’s effectiveness in trying conditions, noting how it is also fitted with the BCDC1225D unit.

“We’ve got an LC79 with a canopy on the back,” he says. “We can be out in the middle of nowhere and have two fridges running and lights and everything else, and the solar panel is just sitting on the roof connected to the charger, charging away and doing all the right things.

“We’ve got cold food, cold beer; everyone’s happy and there are no issues.”

I reckon there’s a certain 4X4 Australia photographer that will be happy, too, knowing she can be in the middle of nowhere and be able to rely on having constant, reliable power ready to go.