Victron Energy Autotransformer - Split Phase 120/240V - 100AMP - ITR000100101 - CW82998

Victron Energy Autotransformer - Split Phase 120/240V - 100AMP - ITR000100101 - CW82998

Autotransformer - Split Phase 120/240V - 100AMP

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.

Temperature protected In case of overheating, the Autotransformer is disconnected from the supply. Reset is manual. 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)

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.

• Step-Up and Step-Down Functions: Easily converts voltage levels to suit different needs, providing flexibility in power management.

• Split-Phase Output Balancing: Balances the load between the two legs of a 120/240V split phase supply, ensuring optimal utilization of the power source. This is crucial when dealing with unbalanced loads, such as those created by different 120V appliances.

• Temperature Protection: Built-in safety feature disconnects the autotransformer in case of overheating, with a manual reset to ensure safe operation.

• Ground Relay for Inverter/Chargers: Includes a ground relay for proper functioning with Multi or Quattro inverter/chargers. This ensures the neutral output is grounded when operating in inverter mode, which is essential for GFCI functionality in a split-phase supply.

• Alternative to Stacked Inverters: Provides a cost-effective and efficient alternative to stacking two 120V inverters for a 120/240V split phase supply. A 240V inverter combined with an autotransformer offers a streamlined solution.

• Voltage Conversion: This autotransformer allows you to efficiently step up or step down voltage between 120V and 240V, optimizing your power system and reducing the load on your inverter.
• High Capacity: With a 100A capacity, it’s suitable for larger off-grid or backup systems, providing consistent voltage regulation for heavy-duty applications like RVs, boats, and residential setups.
• Split-Phase Configuration: Ideal for systems using split-phase 120/240V, ensuring the proper distribution of power across both phases for balanced performance.
• Efficiency and Power Quality: Helps improve the overall efficiency of your power system by balancing voltages, reducing energy loss, and ensuring stable operation of sensitive equipment.
• Built for Durability: Designed to withstand rugged conditions, it’s built with high-quality components for reliable long-term use, making it perfect for off-grid, marine, or industrial applications.
• Seamless Integration: Easy to integrate into existing Victron systems, ensuring smooth operation and maximum efficiency when paired with Victron inverters and other components.

Q: What is the Victron Energy Autotransformer used for?
A: The Victron Energy Autotransformer is designed to convert split-phase 120/240V AC to 120V AC for use in systems with split-phase power, ideal for RVs, boats, and off-grid setups.

Q: What is the output capacity of the Autotransformer?
A: It supports up to 100 amps of output, providing a reliable power conversion for large systems.

Q: What voltage does the Autotransformer handle?
A: It works with split-phase 120/240V AC input and outputs 120V AC, ensuring compatibility with typical household or industrial power sources.

Q: Is the Autotransformer suitable for use with solar or backup power systems?
A: Yes, it can be integrated into solar or backup power systems, optimizing power distribution in off-grid or hybrid setups.

Q: Does it have smart features?
A: While it does not feature Bluetooth, it integrates easily with Victron's other devices for streamlined power management.

Q: Is it easy to install?
A: Yes, the autotransformer is designed for straightforward installation with clear wiring instructions and compatibility with a range of setups.

Q: Does it include built-in safety features?
A: Yes, the autotransformer includes protection against overvoltage and overcurrent, ensuring safe and efficient operation

• Regular Cleaning: Clean the autotransformer periodically using a soft, dry cloth to remove dust, dirt, and debris. Avoid using water or harsh cleaning agents that could damage the device or its components. Ensure that the air vents remain unobstructed to allow for proper ventilation.

• Ensure Proper Ventilation: Install the autotransformer in a well-ventilated area with ample airflow. Ensure that there are no obstructions blocking airflow to prevent overheating. The unit should be placed in an environment with temperature control to maintain optimal operating conditions.

• Inspect Wiring and Connections: Periodically check the input and output terminals for any loose connections, corrosion, or signs of wear. Tighten any loose connections and clean any corrosion to prevent poor electrical contact, which could cause operational issues or inefficiency.

• Monitor Performance: Ensure the autotransformer is correctly balancing the 120/240V split phase and distributing the load evenly across the system. Monitor the system's performance to confirm it’s operating at the correct current (100A max) and voltage levels without overloading.

• Test Functionality: Regularly test the autotransformer to ensure it’s functioning as expected. Verify that the voltage conversion from 120V to 240V (or vice versa) is smooth and stable, with no interruptions or fluctuations that could affect connected equipment.

• Avoid Overloading: Ensure that the system is not exceeding the 100A rating of the autotransformer. Overloading could cause the unit to overheat and potentially damage internal components. Always ensure that connected loads are within the device’s specified limits.

• Check for External Damage: Regularly inspect the external housing for cracks, dents, or other physical damage. Any damage to the casing could affect the safety and performance of the autotransformer. Address any issues promptly to prevent further damage.

• Inspect for Loose Parts: Check the unit for any loose components or hardware that may have come undone during regular use. Tighten any loose screws or fasteners to maintain the stability and safety of the unit.