Keep Cruisin'

powerboat blog 1 teaserPowerboat cruising enthusiasts Neil and Maria bought their 2011 Mustang 2800 Series II, ‘Imagination’, in January 2017 and were looking forward to long relaxing weekends on the water, enjoying the peace and serenity of the open ocean.

But thanks to a sub-par house battery system installed before they bought the boat, they quickly found that the battery levels were dropping below 65% by the end of the day. The conversation soon turned from wondering whether to have red or white wine with dinner, to wondering whether they would have enough battery power to get through the weekend.

“It felt like we were always talking about whether the generator could charge up the batteries, how long we would have to run it, and what we were using most of our power on”, says Maria.

With the risk that running a noisy generator on every trip was going to shatter the peace, and the only new skills they were likely to build were in battery maintenance, Neil and Maria knew it was time to act. The first step was checking their power usage.

Checking Power Usage

It turned out that Neil and Maria’s daytime power usage was pretty modest. The two fridges needed 4 Amps, with the fresh water pump and shower drawing a further 10 Amps each. The stereo needed 5 Amps, though it's seldom used since they relish the peace and quiet. Big draws like the toilet, which needs a hefty 30 Amps for a 15-second flush, are kept to a minimum, and though the bilge pump would need another 10 Amps if it ran itself, it seldom does.

Night time power usage was a different story. Energy efficient LED lights in the cockpit added around 1-2 Amps, and a couple of Targo ceiling lights added another 500 Milliamps. The LED anchor light needs 300-500 Milliamps, which is low but adds up when it’s running all night, and three LED cabin lights, though used sparingly, draw another 500 Milliamps each. And not every light on the boat is entirely functional admits Maria.

“We did install those sexy underwater blue lights on the back of the boat too,” she says, “just because they look good”.

Other equipment proved to be no huge power drain on the house battery system; the VHF Radio, Depth Sounder, GPS, winch and trim tabs are all usually only run when the engine’s running, and the bilge blower only needs 5 minutes’ power before the engine is started.

Until now Neil and Maria have been relying on a Victron BMV-702 Battery Monitor to check the status and remaining power of the start battery and the house battery. They also used it to check how much power an appliance was using by turning everything else off.

Despite that, when KLM Marine Electrics took a look they confirmed the house batteries – calcium batteries designed for hot conditions – were discharging too fast and struggling to hold a charge.

Changing up to a CTEK Power Management System

Queensland is sunny, so it seems logical that any outdoor power sport should harness the sun’s energy since it free. Neil and Maria thought so, that’s why they bought a BAINTUFF Solar Blanket which in peak sun can produce up to 10 Amps, not bad when your daytime usage is 4 Amps. But even with up to 6 Amps of extra charge, they were still struggling to power up the batteries.

The 1KV generator they bought so they wouldn't be left high and dry was great at charging the batteries, but they had to keep it running morning and night, not exactly a fallback. "We only wanted to run the generator every two or three days if possible", says Neil.

It was time to change it up to a new power management system.

Full Speed Ahead with New Batteries and the CTEK D250SA + SMARTPASS120

With the help of KLM Marine Electrics, Neil and Maria settled on a new power management system that included:

•Three new 120 Amp AMG house batteries

•Replacing the 110 Amp start battery with a smaller 70 Amp battery to offset some of the weight gains from the new house batteries

•The CTEK D250SA and CTEK SMARTPASS120 DC-DC power management system

It proved to be the right choice for maximising battery power on the water, and Neil and Maria were back chatting about wine options and enjoying the peace and quiet on their very next weekend away.

“The new system has made a massive difference for us”, says Neil, “we were able to charge our batteries to capacity while driving, and top up the charge with the solar blanket when we were at anchor”.

Neil and Maria were also surprised to discover the SMARTPASS 120 boosted the charging capacity of the solar blanket from 10 to 16 Amps, enough to cover daytime usage and top up the battery on most days, not just in peak sun.

And with all this battery power on offer, there was no need to use the generator since the batteries didn’t drop below 92% charge at any point on the weekend.

The CTEK Power Management System in Place and Performing

Anyone who owns a boat will tell you they cost money, so anything that saves cash in the long run must be a good thing.

“AGM batteries are a bit expensive, so we wanted to look after them, and not have to replace them too often," says Neil.

The D250SA is a 5-step charger, so when the batteries get close to capacity they optimise the charging rate, slowing the voltage to maintain the battery at full or near full charge; this means they last longer and perform better.

Combining the CTEK D250SA with the SMARTPASS 120 also means Neil and Maria can get the maximum available power from their three new 120 Amp house batteries while it’s on the water. This is especially important since the boat is housed in dry storage where they can’t run a maintenance charger because it’s a fire risk. It also gives them peace of mind when they are out at sea.

IMG 1322 fish“When you’re on the water reliability and safety are critical, so it was also important to have a high-quality DC-DC battery management system we could trust”, says Maria.

CTEK power management systems are trustworthy and powerful, and in fact, this system can charge up to an 800Ah bank of batteries at 140 Amps which makes it unique in the market.

It's also simple to install, and although it ended up the cockpit power cupboard, it would sit just as comfortably in the engine bay thanks to a temperature sensor that compensates for hot or cold conditions.

Ultimately for Neil and Maria, it's about knowing they'll always be able to generate enough power without fuss, or the need to shatter the silence with a generator.

 “We’re very happy that we can just relax and not worry about the battery system anymore”, says Maria, “its automatic, all I need to do is plug in the solar blanket at anchor and pack it away when we head off. How easy is that?”



The CTEK 12V battery management system includes the CTEK D250SA and the CTEK SMARTPASS120.

The CTEK D250SA is a fully automatic, 5-step DC-DC charger that supplies up to 20Amp of power to charge, condition and maintain your 12V lead acid service batteries via your alternator (as you drive) or solar (at anchor). It has:

• A special AGM function for AGM batteries which need to be charged at a higher voltage of 14.7V.

• An advanced inbuilt Maximum Power Point Tracker (MPPT) that maximises the power from your solar panels, saving time and money since there’s no need for a separate solar regulator.

• A temperature sensor that compensates for either hot or cold conditions, virtually eliminating the risk of your battery overheating or overcharging.

The new SMARTPASS120 is a fully automatic, 120A on-board power management system. When using the CTEK D250SA + SMARTPASS120 together, they become the ultimate power management system delivering up to 140Amps of charging power to an 800Ah battery bank while you’re on the move.

BAINTUFF 180W Foldable Solar Blanket

The BAINTUFF 180W Foldable Solar Blanket is a lightweight, compact solar blanket that doesn’t need an aluminium frame, so it's quicker and easier to set up on board. It’s weather resistant and it won’t scratch your paintwork, and can easily be repositioned to soak up every last ray as the sun moves across the sky during the day.

A whopping 180W of power means the BAINTUFF 180W Foldable Solar Blanket gives you more bang for your buck since you'd need over 12kgs of traditional fold out solar panels to get the same amount of power. And it will still pump out up to 75% of its max output as the day draws to a close.

Here are the at-a-glance specs for the BAINTUFF 180W Foldable Solar Blanket






5.5V/2A & 18V/10A

Rated Power

18V 180W

Unfolded Size

398*300*78mm / 15.67*11.81*3.07 inches


5.11kg / 11.26lbs / 180.23 oz.



Voltage regulator to stabilise current


Built-in USB IC for quicker phone charging across all mobiles



One year from date of purchase (excludes accessories)

About Us

Bainbridge Technologies is one of Australia's leading Expert Power Systems Wholesaler...

Bainbridge Technologies brings together more than 30 years of DC and AC power systems expertise and reliable, world class products to support your business objectives with specialised off-grid power storage systems.