Section 6: Multistage Charging

The Prosine inverter/charger has a fully functional multistage battery charger. Any time an acceptable (within frequency and voltage parameters) AC source is presented to the unit, it will charge the batteries connected to it. When AC is present and the charger is enabled, the charger will charge the battery bank regardless of the position of the inverter’s On/Off switch.

Charging Profile

The battery charger in the Prosine charges in three stages—BULK, ABSORPTION, and FLOAT— to provide rapid and complete charge cycles without undue battery gassing. The figure below shows how DC voltage and current change with time through the different charge stages.

 

 

Bulk

Absorption Charge

Float Charge

Charging

Bulk Volts Setting

 

Started

 

 

 

Float Volts Setting

 

 

 

 

DC Voltage

 

 

DC Current

Time

Constant Current

@ Maximum

Charge Rate

Constant Voltage

Reduced Voltage

Load current on demand

Figure 7. Three-Stage Charging Profile

Bulk Charge

In the first step, known as the bulk charge, the Prosine inverter/charger delivers the maximum charge current allowable given the configuration settings, that is, battery type and temperature, maximum AC input setting and battery bank size. This current is delivered to the batteries until the battery voltage approaches its gassing voltage—typically around 14.4 volts for 12 volt batteries and 28.8 volts for 24 volt batteries (again this voltage can vary depending on battery type and other settings). The bulk charge step restores about 75% of the battery's charge. The gassing voltage is the voltage at which the electrolyte in the battery begins to break down into hydrogen and oxygen gases. Under normal circumstances, a battery should not be charged at a voltage above its gassing voltage since this will cause the battery to lose electrolyte and dry out over time. Therefore the Prosine inverter/charger transfers to the next stage, known as the absorption charge.

Absorption Charge

During the absorption charge, the charging voltage is held constant near the gassing voltage and the charging current is steadily decreased. When the charging current has decreased to a predetermined

Prosine 2.5/3.0 Installation & Operation Guide

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Xantrex Technology PS2.5, PS3.0 Multistage Charging, Charging Profile, Bulk Charge, Absorption Charge

PS3.0, PS2.5 specifications

Xantrex Technology has made significant strides in the power electronics sector with the introduction of their PS2.5 and PS3.0 inverter models. These inverters are designed primarily for solar energy applications, offering reliable and efficient power conversion for residential and commercial solar installations. The PS series stands out in the market due to its advanced features, innovative technologies, and user-friendly characteristics.

One of the main features of the Xantrex PS2.5 and PS3.0 inverters is their high efficiency rating, typically above 97%. This means that a minimal amount of energy is lost during conversion, allowing users to maximize their solar energy utilization. Additionally, these inverters come with a wide input voltage range, making them versatile and capable of handling various solar panel configurations.

Both models are equipped with advanced MPPT (Maximum Power Point Tracking) technology. This feature optimizes the energy output from solar panels by constantly adjusting the operating point to ensure maximum power is extracted, even in variable weather conditions or partial shading. This capability significantly enhances the overall energy harvest from solar systems.

Another notable characteristic is their compact and lightweight design, which facilitates easy installation and integration into existing systems. The inverters are also designed with robust thermal management solutions, ensuring they operate effectively even in high-temperature environments. This durability extends their lifespan and increases reliability, critical factors for any solar installation.

Xantrex has also prioritized user experience with the PS2.5 and PS3.0 models by providing a built-in monitoring system. Users can access real-time data on energy production, performance metrics, and system status through a user-friendly interface. This connectivity allows for quick troubleshooting and maintenance, thus enhancing the overall efficiency of solar energy systems.

Safety is paramount in the design of these inverters. They meet stringent international safety standards and come equipped with comprehensive protection features, including over-voltage, under-voltage, and short-circuit protection. This ensures the inverter operates safely, protecting both the user and the connected solar array.

In summary, Xantrex Technology's PS2.5 and PS3.0 inverters are engineered with cutting-edge features and technologies that cater to the evolving needs of solar energy users. Their efficiency, adaptability, and focus on safety make them an excellent choice for those looking to invest in renewable energy solutions. As the demand for sustainable energy continues to rise, Xantrex is poised to play a significant role in the market with these innovative inverter solutions.