Description
About This Product
The Fronius 35 Amp Three Phase Backup Controller is a three phase automatic switching unit used in Fronius full backup power systems. It is designed to disconnect the site from the public grid during a grid failure and switch the installation into backup operation where the connected Fronius hybrid inverter and battery system support the loads. When the grid returns, it automatically changes the system back to normal grid-parallel operation.
This model is intended for fixed installation in suitable switchboard arrangements and is used with compatible Fronius GEN24 Plus and Verto Plus systems where automatic full backup switching is required.
Product Explainer Video
How-To Video: Fronius Backup Switch – Installation & Commissioning
Who This Product Suits
The Fronius 35 Amp Three Phase Backup Controller suits three phase residential or light commercial Fronius backup installations where the customer wants automatic changeover rather than a manual backup switch.
It is best suited to systems using compatible Fronius hybrid inverters and battery storage, especially where the installer is designing a full backup solution for selected site loads or whole-site backup within the approved system limits. It should be selected and installed by a licensed electrical contractor in line with Fronius documentation, local wiring rules and network requirements.
Specifications Explained
The Fronius 35 Amp Three Phase Backup Controller is rated for three phase operation with a nominal current of 35 A, nominal voltage of 400/230 V and nominal power of 24 kVA. It operates on 50 Hz mains supply and is intended for TN-S and TN-C-S grid types.
The controller provides 3-pole disconnection and includes FRT capability. It is certified to IEC 60947-6-1 and has an IP20 protection rating, making it suitable for protected switchboard installation rather than exposed outdoor mounting. Compatible Fronius inverter families include Primo GEN24 Plus, Symo GEN24 Plus and Verto Plus models within the supported backup system range.
Summary
The Fronius 35 Amp Three Phase Backup Controller is the correct Fronius switching component for eligible three phase full backup installations where automatic transfer between grid operation and backup operation is required.
It is a practical option for installers building Fronius battery backup systems, provided the inverter, battery, switchboard design, grid type and network approvals are all suitable for the job.
Further Information From The Manufacturer
The Fronius 35 Amp Three Phase Backup Controller by Fronius is a fixed piece of equipment designed for use in public grids with TN-C-S/TN-S systems. Its main function is to automatically and securely disconnect all connected loads and generators from the public grid in the event of a grid failure or grid malfunction in accordance with the specifications of the grid operator. The Fronius P-FRO-BACKUP-CONTROLLER is required for systems with storage batteries to enable automatic backup power switching. It can be installed either on an indoor DIN rail or in special enclosures with corresponding IP protection, depending on the environmental conditions. See more about the Backup controller at Fronius
Key Features
- Application: The Fronius Backup Controller is required for systems with storage batteries to enable automatic backup power switching
- Installation: Installed either on an indoor DIN rail or in special enclosures with corresponding IP protection, depending on the environmental conditions
- Safety precautions: In conjunction with a Fronius Smart Meter, corresponding back-up fuses must be selected to suit the cable cross-sections of the copper conductors and the maximum current of the Fronius Backup Controller
- Intended use: The Fronius Backup Controller must only be operated in accordance with the specifications in the enclosed documentation and in accordance with local laws, regulations, provisions, standards and within the limits of technical possibilities
Main Benefits
- Automatic Backup Power Switching: Enables automatic backup power switching for systems with storage batteries
- Grid Failure Protection: Automatically and securely disconnects all connected loads and generators from the public grid in the event of a grid failure or grid malfunction
- Flexible Installation: Can be installed either on an indoor DIN rail or in special enclosures with corresponding IP protection, depending on the environmental conditions
- Compliance with Grid Operator Specifications: Operates in accordance with the specifications of the grid operator
- Convenient and Secure Operation: Automatically reconnects loads and generators to the public grid once grid stability has been restored
Weights & Measurements Information
| Weight (kg) | 0.6250 |
| Length (mm) | 144 |
| Height (mm) | 100 |
| Width (mm) | 65.6 |
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About Fronius
Fronius is a long-established European manufacturer known for high-reliability inverters used in residential and commercial solar systems. Founded in 1945 and still family-owned, the company designs and builds its inverters with a strong focus on durability, serviceability and long-term product support.
Fronius is recognised in the industry for its active cooling approach, robust monitoring platform and strong technical presence in Australia. Their inverter platforms are widely used by installers who prioritise performance, clear diagnostics and long service life.
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