Victron Autotransformer 120/240V-100A - ITR000100101
Click Here for Warranty Enquiries
The SSB Lithium Starting Battery range is the pioneer of lithium starting batteries in Australia. Our cutting-edge research and technology have been leaders in Australia in innovating, researching, and testing lithium batteries for over 12 years. We have also purchased and tested almost every other major brand of lithium starting batteries from around the world and have designed SSB Lithium Starting Batteries to be superior in every aspect.
Victron Energy has a strong, unrivalled reputation for technical innovation, reliability, and build quality. Our products are widely considered to be the professional choice for independent electric power.
Shipping for any standard item is generally within 3-5 business days. Some bulkier items or special order products from certain suppliers (i.e: Victron) may take longer depending on stock at the vendor’s warehouse. You will be kept up-to-date via email.
About Trade Pricing
Reliable batteries at great prices. With MBC you get the convenience of online ordering, with hundreds of nation-wide in-store locations in the event of a warranty issue. Our batteries are used throughout the marine industry - including by our own marine electrics business - so we only sell high quality products. If you have any questions about our products, or want help figuring out what’s best for you, our team of industry experts are happy to chat.
Victron Autotransformer 120/240V-100A - ITR000100101
The Autotransformer: for step up, step down and split phase balancing
An autotransformer can be used for step up, step down and split phase output balancing purposes. While the step up and step down functions are fairly straightforward, split phase output balancing may require some more attention.
Consider for example a 30A 120/240V split phase supply. The supply could be the grid, a generator or two stacked inverters. Some of the loads connected are 240V, others are 120V. On each 120V leg the load should not exceed 30A. The problem is that as soon as 120V loads are connected, the two legs will show a different current. This is because the 120V loads on the two legs will never be balanced. A 120V 1200W hairdryer, for example, will draw 10A from one leg. A 120V washing machine could even draw in excess of 20A from one leg. Between the two legs the difference in current, or current unbalance, will therefore often be 20A or more. This means that the 30A supply will not be used up to its full potential. By the time one leg draws 30A, the other leg may be drawing no more than 10A, and increasing the 240V load, for example, will result in an overload of one leg while the other leg still has spare capacity.
Theoretically, the total power that can be drawn from a 30A 120/240V supply is 30 x 240 = 7,2 kVA. In case of 20A unbalance, the practical maximum will be 30 x 120 + 10 x120 = 4,8kVA, or 67% of the theoretical maximum.
The solution is an Autotransformer. By leaving the neutral of the split phase supply unused, and connecting an Autotransformer to create a new neutral, as shown in figure 1, any load unbalance is ‘absorbed’ by the Autotransformer. In case of a 30A supply, the load can be increased to 7,2kVA, and a 20A load unbalance will result in one leg supplying 40A, and the other leg 20A. The 20A difference will flow through the neutral and the windings of the Autotransformer. The current through both 120V wires of the split phase supply will be 30A.
Ground relay for use with Multi or Quattro Inverter/Chargers included
When operating in inverter mode, the neutral output of the inverter/charger must be connected to ground to guarantee proper functioning of a GFCI. In case of a split phase supply the neutral must be grounded. For this purpose a grounding relay is built in the autotransformer’s enclosure. The relay is controlled by the 230/240V Multi or Quattro. (The internal grounding relay in the 230/240V Multi or Quattro must be disabled)
In case of overheating, the Autotransformer is disconnected from the supply. Reset is manual.
An alternative to stacked inverters
The alternative to stacking two 120V inverters to provide a 120/240V split phase supply is a 240V inverter with an additional Autotransformer.
Two stacked 120V 3kVA inverters will supply up to 25A to each 120V leg. If the load on one leg is less than 25A, the maximum load on the other leg is still limited to 25A. One 240V 5kVA inverter with a 32A Autotransformer will supply up to 21A of balanced load to each 120V leg. Fewer loads on one leg will however result in more power being available on the other leg, with a maximum unbalance of 32A.
Therefore the load can be up to 38,5A on one leg if the load is not more than 3,5A on the other leg (maximum unbalance: 38,5 – 3,5 = 35A). If load unbalance is to be expected, a lower power 240V inverter with autotransformer will therefore be preferable to the stacked inverter solution.
Become A Trade Partner
We pride ourselves on transparency and a doors-wide-open type of attitude. If you’re looking to get into the marine battery world, we’re here for you. Anyone can sign up to become a trade partner with us for free and get discounts applied right away.
Our customers can trust us to deliver on the promises we make. Using practical knowledge from 15 years of experience in the industry, we’ll recommend products that we know won’t fail you when you need them most.
We want to provide all our customers with quality products for great prices, while always being honest and transparent with what products fit their vision, big or small.
As experts in our field, with years of hands-on experience, we know batteries like the back of our hands. When you come to MarineBatteryCo. we’ll use that knowledge to your advantage.
Who We Are
With 15 years in the marine industry, and 10 years running our own company, we know batteries and what you’ll need for your goals. With us, you’ll get quality and good value for your money. Our aim is to always deliver on our promises, and never promise more than we can. We’ll tell you the truth, whether it goes above or below your budget. Learn more about Thomas and MarineBatteryCo. here.
So far appears to be a good thing.
Absolutely amazing product. Haven’t had a battery so compact powerful and suited perfectly to vehicle
Easyship Shipping Protection
Great price with quick delivery, very happy and will be a returning customer. 10/10
Ordered the Victron 500A SmartShunt. Not only did these guys give the best price but provided free delivery, which was very fast.
Highly recommend using this company, and I will be a returning customer for sure.
Works as expected from victron
Unreal battery and helpful service to work out which size would suit my application.
Customer service was excellent. Called and was given assistance on what I also needed for my setup and was given an unbeatable price!
Great charger works well , blue tooth connection range is not that great . Over all great unit .
Stoked with my set up of 2x 100Ah Fusion in series!
Thank you for the advice and talking me through installation! Legends.
Victron SmartShunt 500A
Excellent communication and service. Great battery. Well done!
Although I haven’t used them yet the seem a quality product
Installed second smart solar mpg for the portable panels and synced together. So now the roof and portable panels work more efficiently. Can monitor power coming in on Bluetooth phone.
Easy shopping and quick service and I will only shop online using PayPal so well done Marine Battery Co.