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Fronius CL 55.5 Delta Inverter

3-Phase Inverter for Commercial Solar Systems
Rated up to 55,500 watt 3-Phase AC output
Input Power (DC)
Fronius Model Number CL 55.5 Delta
Max. DC Power (STC) 65,000 W
Max DC Voltage 600 V
MPPT Voltage Range 230V - 500V
Max. Input Current 256.7 A
Inverter Efficiency 95.9%
CEC Efficiency 208 V: 94.5%
240 V: 95%
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Fronius CL Inverters

Fronius CL 55.5 Delta Inverter

Fronius Solar

Fronius CL 55.5 Delta 3-Phase Inverter

Commercial grade solar inverter for 208V and 240V AC power.

CL 55.5 Delta inverter connection area
The Fronius CL 55.5 Delta inverter has a spacious, easy to manage system connection area.

Multiple power stages operate in the Fronius CL 55.5 Delta inverter that accomplish something great together with MIX™ technology. This combination of several power stages has many advantages: maximum earnings in partial load ranges, high system stability, long service life, and easy servicing.

This model is selectable between 208V and 240V three-phase AC power for utility grid-tie solar system applications.

Solar system design planning and installation is easy.
The Fronius CL 55.5 Delta inverter was designed with practicality in mind. It can be used for many different configurations due to its planning flexibility. It is also easy to set up due to numerous design details that make installation and connection as simple as possible.

Designed for indoor and outdoor installations.
This inverter has a well designed durable NEMA 3R rated weatherproof, powder-coated aluminum enclosure. Fronius CL inverters are tested and approved to operate in temperatures up to 122°F.

Automatic HF Transformer switching
Fronius transformer inverters like the CL 55.5 Delta use a high-frequency (HF) transformer. The automatic transformer switching function in the produces three efficiency peaks. The result: A constant level of efficiency across the entire input voltage range, resulting in higher yields. Other key advantages of HF transformer technology are a compact, lightweight design, and safety as a result of the galvanic isolation.

Wide input voltage range
Different module configurations are possible: The wide input voltage range ensures high flexibility for system configuration.

Extensive system monitoring
System monitoring is vital for inverters of this size. Using the comprehensive Fronius DATCOM system, you can set up a complete monitoring system including extensive data recording, analysis, visualization as well as remote monitoring.

Equipment Features

  • Inverter system design with MIX™ technology
  • Automatic HF transformer switching
  • High-yield power electronics
  • Intelligent cooling
  • 208V / 240V AC selectable
  • Simple system planning and easy installation
  • Comprehensive system monitoring
Delta Power Stage

Fronius CL 55.5 Delta Central Inverter Review

Unique system design with the Fronius MIX concept. 
Multiple power stages operate in the Fronius CL 55.5 Delta inverter. Fronius MIX™ Technology is the clever combination of these multiple power stages that allows Fronius inverters to always achieve maximum yield, even with partial-loads. This is due to the unique Fronius Master Inverter X-Change system (MIX), a development of the classic master/slave principle. How it works: All power stages are equal. The “master” is allocated alternately, depending on the operating hours. The result is that loads are applied evenly to individual power stages decreasing operating time on any one power stage.

Maximum efficiency under partial load
With MIX technology, get the maximum power harvest out of partial load ranges, e.g. on cloudy days, through a clever combination of multiple power stages in each inverter. The power stages in Fronius inverters divide up the work depending on operating hours and only operate as many power stages as required to efficiently process available power from the PV array. Fronius MIX™ technology provides more yield.  Depending on the level of available power, either one or up to all power stages work together.  Advantages include higher yield during partial load conditions and significantly reduced operating hours. Read more on our Fronius inverters page.

Unrivalled stability
The redundant Fronius solar design of their inverters means that even if one power stage fails, the inverter continues to operate, ensuring yields are achieved. In the unlikely event a power stage fails the others will continue to operate.

Longer service life
Depending on the operation hours of each power stage, our inverters decide which power stages run under partial load conditions. This ensures that the work load is distributed equally between the power stages. The result is reduced operating time of individual power stages which increases the lifespan of the inverter.

Fronius Module Manager
Whatever solar panel array you decide on, whether monocrystalline, multicrystalline or thin-film, this inverter always fits perfectly in the system-concept. The "Module-Manager" is software integrated into each Fronius CL inverter that optimizes the earnings of your system in each and every situation. The Module-Manager does a first class job and leads to optimal results.

Simple planning, easy installation
The Fronius CL was designed with practicality in mind. It can be used for many different assignments due to its planning flexibility. It is also easy to set up due to numerous design details that make installation and connection as simple as possible. The universal compatibility with all solar panels and wide voltage range make this inverter a smart choice for most solar system designs. What makes this inverter even more appealing is the intuitive operation and ease of use, together with its highly informative analyses of system values in every situation.

Intelligent cooling
An innovative ventilation design eliminates dust and moisture from getting into the power stage area. The air required for cooling is drawn in by two fans on the front of the device and passed through a closed channel through the individual power stages. The electronic components never come into contact with the outside air.  Inside the airtight power stage a smaller fan ensures uniform cooling. This sophisticated system increases the operational reliability and the service life of the inverter.

Datalogging & Monitoring Options

Monitoring using Signal Card

• Monitoring using Personal Display
• Monitoring with Fronius CL DatCom

Additional components

• Fronius CL Public Display
• RiCo Display with Public Display Card
• Sensors with Sensor Card

Combination of components

• Public Display + Sensor Box
• Public Display + Sensor Box + FRONIUS SolarWeb + Fronius CL.message
• String Control (ideal for Fronius CL central inverters)
• String Control + Basis DatCom

info Fronius Datamanager Datasheet

Fronius configuration tool
The Fronius configuration tool is safe, easy and just requires a common Internet browser.

Fronius Configuration Tool

Comprehensive & User Friendly - For the perfect sizing of your PV system.
In the planning stage of a PV system, the Fronius Configuration Tool supports you in the best possible way to get the perfect sizing. Just complete the input fields and you will quickly get charts of the different configuration possibilities. Solar Electric Supply has been designing solar inverter systems for over 15 years. Contact our knowledgeable staff with any other questions you may have about solar system design.

System Requirement for using Fronius Configuration Tool
Internet browser: Firefox, Chrome or Microsoft Internet Explorer 6.0 equivalent or newer.
Download configuration tool

Disclaimer:  The Fronius Configuration Tool was developed by Fronius to assist Users with system designs but does not guarantee the configuration is appropriate for your use. By using the Fronius Configuration Tool, the User claims all responsibility for the accuracy and validity of the results including, but not limited to, system design, performance, and code compliance. It is incumbent upon the User to verify that the system design will meet their site-specific needs and local codes. 

Contact us toll-free at (877) 297 0014 for expert assistance with any commercial Fronius solar inverter system design.