Victron Energy Autotransformer Table of Contents 1. Safety ................................................................................................................................... 1 2. Introduction ........................................................................................................................... 2 2.1. Description ................................................................................................................... 2 2.2. Models ........................................................................................................................ 2 2.3.

Types of Use ................................................................................................................. 2 2.3.1. Balancing ........................................................................................................... 2 2.3.2. Stepping Up Voltage .............................................................................................. 4 2.3.3. Stepping Down Voltage ........................................................................................... 5 2.4. Ground Relay ................................................................................................................ 7 2.5.

Temperature Protected ..................................................................................................... 7 2.6. Over Current Protection .................................................................................................... 8 2.7. Sizing Limitations ............................................................................................................ 8 3. Installation ............................................................................................................................. 9 3.1. Installation Considerations ................................................................................................. 9 3.2.

Mounting ...................................................................................................................... 9 3.3. Wiring ......................................................................................................................... 9 3.4. Conduit ....................................................................................................................... 9 4. Specifications ....................................................................................................................... 10 5. Enclosure Dimensions ............................................................................................................ 11 6.

Warranty ............................................................................................................................. 12

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1. Safety

Victron Energy Autotransformer 1. Safety These instructions are for use by qualified personnel only. Do not perform any servicing or installation other than that specified in the operating instructions unless you are qualified to do so. Incorrect installation or servicing may result in a risk of electric shock, fire, or other safety hazards. All electrical work should be performed in accordance with local and national electrical codes. This product is designed for indoor/compartment installation. Use insulated tools to reduce the chance of electrical shock or accidental short circuits. Select the wire size based on the protection provided by the circuit breakers.

Before making any connections verify that the circuit breakers are in the off position including the inverter breaker. Double check all wiring before applying power. The following safety symbols have been placed throughout this manual to indicate dangerous and important safety instructions. CAUTION: This symbol indicates that failure to take a specified action could result in damage to the equipment. Info: This symbol indicates information that emphasizes or supplements important points of the main text. Page 1 Safety

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2.3.1. Balancing

Victron Energy Autotransformer 2. Introduction 2.1. Description The Victron Energy Autotransformer (AT) supports many different wiring configurations. It can increase your system’s ability to adapt to different design and Voltage requirements, and also be used to balance loads in split-phase 120/240Vac systems. Specialty systems such as boats and vehicles may face different shore configurations while traveling, an autotransformer can help by being flexible and enabling connections to most grid configurations.

The Victron Energy Autotransformer has the ability to use a ground/earth relay to create a Neutral to Ground bond in the AT itself, if coupled with a Victron Energy MultiPlus or Quattro and the relay terminals are interconnected. This manual will explain the many uses for this device and how to safely install and wire it. Below there are general examples of four ways the Autotransformer can be applied. There are several specific uses that can be realized in the integration of an autotransformer into an installation and are explained in section 2.4. The AT does not provide isolation. See section 4 for specifications. 2.2.

Models 120/240V - 32A 120/240V - 100A Pass through current is 32A and 100A respectively, the transformers are 100% equal in both models. See more information in section 2.7. 2.3. Types of Use 2.3.1. Balancing Balancing a Generator or Stacked Inverters Full power from a split phase supply source such as a generator or stacked inverters is sometimes limited, as a single phase load cannot draw more energy than its individual leg will allow even though the other leg isn’t fully utilized. If balancing a generator or stacked inverters is required, the AT can accomplish this by leaving the neutral of the split phase supply unused, to create a new neutral, as shown in the illustration below.

Any load unbalance is “absorbed” by the autotransformer. The two legs of a split phase from an AT are independent from each other, beside the fact there is a fixed phase shift between them. This (180Deg) phase shift means the sine-wave of both legs is in full opposite (creating a double voltage from leg to leg rather than that of leg to Neutral). With an AT, energy from one leg can be “transferred“ to the other leg which creates a far higher total load level, unlocking the full potential of power available from a generator or stacked inverters.. Page 2 Introduction

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2.3.2. Stepping Up Voltage

Victron Energy Autotransformer 2.3.2. Stepping Up Voltage Alternative to Stacked Inverters. Loads such as deep well water pumps and air conditioning units sometimes require Split-Phase 120/240Vac power. When the available AC power source is not what is needed in the installation, the autotransformer can create the needed voltage by doubling the incoming voltage. The alternative to stacking two 120Vac inverters to provide a 120/240Vac Split-Phase is a single 120Vac inverter with an additional autotransformer. Other possible cases for stepping up the Voltage are shown in the wiring diagrams below. Page 4 Introduction

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