There’s a lot more to a camper trailer’s electrical set-up than batteries. DC to DC and 240V chargers, inverters, and battery management and monitoring systems add to the complexity. It can be hard to wrap your head around what each and every bit of electrical kit does.
At REDARC Camper Trailer of the Year, I caught up with Haydn, a qualified automotive electrician who is part of the tech support team at REDARC. It’s a big team, with usually six or seven people providing support over the phones, email and online on any given day.
Haydn’s level of experience is no exception. REDARC’s Managing Director Anthony Kittel tells us it’s part of the brand’s philosophy: “We want to make sure the people at the coalface are passionate about the industry and immersed in it, so they can talk to the customer and understand their requirements.”
Haydn brought along all of the gear and was also able to show me it in action in some of the camper trailers present, such as the Patriot and Ultimate. Turns out, the electrical devices you find in your camper are actually pretty straightforward, when you’re talking to someone who knows their stuff and is able to put it in easy-to-understand terms.
DC to DC Chargers
REDARC’s 12V DC to DC charger range, known as BCDC (BC for ‘battery charger’, DC for ‘direct current’), starts with the BCDC1206 and goes right up to the 1250D. These chargers are mounted near your auxiliary battery (either your camper’s or your car’s) and charge it up using 12V DC input, which comes from the car’s alternator and solar input (for the dual input models).
The numbers after ‘12’ refer to how many amps the charger can charge the battery by per hour at its maximum. Haydn says that for a single battery application, as seen in many camper trailers, the 25D is perfect. But, for anything over 180Ah total, he recommends going to the 40D or 50D. He says it’s best to check the battery specs too, to ensure your battery can cope with the amount of charge you plan to put into it.
BCDC chargers have ‘green power priority’, meaning they prioritise solar power, and then draw only the extra power that is required from elsewhere. The dual input models are compatible with all battery types, including lithium.
240V AC to DC Chargers
The South Aussie brand also offers a range of AC to DC chargers, known as SmartCharge. These take a 240V AC (‘alternating current’) power source, which is what you get from a standard powerpoint, and convert this power so it’s suitable and then use it to charge your battery. This type of charger is handy to keep in your glovebox as ‘insurance’ against dead batteries that are getting low despite DC to DC charging, Haydn says.
In his own words, “Many campers have off-grid systems without 240V charging. Such campers may get caught out and need to be able to jump into a caravan park and charge up. Once you’re there it’s very easy. You connect the charger to a powerpoint, attach it to the two battery terminals, then turn it on. That’s it.”
SmartCharge AC Chargers come in 4, 6, 8 and 10 amp models. The 8 and 10 amp models suit bigger batteries, like you’d find in your camper trailer. Haydn says the 10amp is best suited for battery set-ups up to 250Ah.
Once the battery reaches full charge, the charger, if kept connected — say while your camper is sitting in the garage — will go to sleep for a week then turn on again in a week’s time and either start charging again or fall back asleep for another week. Not charging continuously is important because otherwise you can, to put it crudely, ‘cook’ your batteries.
Battery Management Systems
REDARC are renowned for their Battery Management Systems (BMS), such as the Manager30. This model is a 30 amp DC to DC charger and AC to DC charger all in one. It can take three inputs — 240V from a powerpoint, 12V from the vehicle’s alternator, and solar from a panel — to top up your batteries. Having everything in one place and not having to worry about two separate chargers is one of the main appeals, Haydn says. As with the BCDC range, the Manager30 has green power priority.
The Manager30 comes with a remote monitor that can display what percentage of charge the battery/s currently has. You can see how many amps are being drawn and how many the BMS charger is putting back into the battery. Using this information, the Manager30 can determine if you are ‘covered’ — that is, maintaining consistent charge or gaining it. In cases where outgoing current exceeds incoming current, the BMS can calculate, using the live figures, how many days or hours you have left before the batteries go flat.
The Manager30 can also log and track the amount of charge you’ve had per day or per hour from solar or DC and the state of charge over time. It also features load disconnect, meaning the installer can load in a solenoid and have the battery disconnect the load to certain power-drawing items, such as lights, if the charge drops below a certain point, while keeping others, such as the fridge, going.
Total Vehicle Management Systems
The RedVision TVMS (Total Vehicle Management System) can be added to the Manager30 for the ultimate set-up. As Haydn explains: “It’s not a charger; it’s our distribution box. It’s all your fusing, switches and relays in one location. We’ve got 10 amp circuits and 30 amp circuits that we can use to switch absolutely anything we want to, whether that’s lights, water pumps, fans or fridges.”
When coupled with a Manager30, the RedVision TVMS provides readings on a sophisticated, coloured screen, such as amps in and out and how many days or hours until flat. On top of this, RedVision has the capability of connecting with up to six water tank sensors and displaying water levels. Same goes with the two temperature sensors and even your breakaway system (the RedVision can be set so you receive a warning when the breakaway battery is flat). All data that appears on your RedVision appears on your phone too, thanks to its bluetooth functionality. Within range, you can see all the data it provides. You can also control circuits remotely; you can turn things on and off using just your phone.
Haydn says that while advanced data access and the ability to remotely control are the main appeals for camper trailer owners, the ability to customise circuits and show simple install makes the RedVision most appealing for manufacturers.
Inverters are the opposite of the converters used in REDARC’s 240V chargers. Their 12V inverters take the DC power output of your deep-cycle battery and turn it into 240V AC power, so you can power the devices you traditionally use at a powerpoint at home (inverters have a powerpoint on them so you can simply plug in). REDARC also offers 24V inverters.
Inverters are rated in terms of how many watts of power they can provide at any given time. REDARC’s range of 12 and 24 volt inverters starts at 350 watts and reaches 3000W. In the camper trailer industry, you rarely see anything bigger than 1500 or 2000W. The correct size depends on the individual’s power needs or what sort of devices the camper trailer needs to run. Haydn says that a 1500W inverter is enough to run a small nespresso machine and a small toaster. A 350W inverter on the other hand will only be able to run camera, phone, laptop and other small battery chargers. Because the process of transforming the current chews at your charge levels itself, inverters are best suited to battery banks with higher amp hour capacities.
REDARC inverters feature in-built protection; if you plug a device needing 3000W into a 350W unit, you won’t damage the inverter; it will just not provide the power. The RedVision can be paired with REDARC inverters, so you can turn it on and off on your phone and see its wattage output to know how much more you can plug in or whether you’re pushing it.
All REDARC inverters are pure sine wave, as opposed to modified sine wave. What that means for the consumer is that you’ll be able to power all devices, even the more sensitive ones, like some TVs.