Fire department switch Safety: The construction of a large-scale PV power plant with a total output of 4.7 MWp on the roofs of the Ladenburger factory in Bopfingen represents a significant step towards sustainable energy generation. Since the beginning of May 2023, e.systeme21 has been working on this forward-looking project, which not only overcomes ecological but also technical challenges.
Optimization of energy requirements
The experts at e.systeme21 developed a customized system concept that takes into account the company's annual and daily electricity requirements. The plant extends over three large roofs with trapezoidal sheet metal roofing and a large flat roof, and comprises 11,191 modules on a total area of over 22,500 m². The system is adapted to the company's electricity requirements in order to achieve maximum yield.
The challenge of feed-in power
Despite the high generation capacity, the responsible grid operator only permitted a feed-in capacity of 30 kW, which corresponds to a zero feed-in. In order to meet this requirement, a certified process for regulating the feed-in power was established, which is supplemented by redundant safety shutdowns.
Safety as the top priority
Particular attention was paid to fire department counter safety, especially the protection of firefighters. The cables are laid on traverses and routed through Q3 fire department switchboxes, which enable both central disconnection - via the fire alarm control panel - and decentralized disconnection - at each relevant traverse. This allows the firefighters to carry out their extinguishing operation safely. It is even possible to safely tear off traverses, should this be necessary for the success of the extinguishing operation.
Fire department switch Safety
There were several reasons for choosing the QFire PV fire switches from Q3:
- High number of DC strings possible, beyond the competitive standard.
- Overvoltage protection up to 1500 V.
- High switching current of 15 A per line.
- Remote switching option.
- Expert discussion partners with extensive knowledge of large-scale PV projects.
- Communication in German for clear understanding.
- Proximity of the companies.
- Delivery reliability and production quality confirm the decision in the implementation.
- QFire PV fire circuit breakers from Q3 Energie are considered the gold standard in generator disconnection and are therefore used to protect large-scale projects.
The use of QFire PV fireman's switches from Q3 Energie not only ensures the safe operation of the PV system, but also protects people and property in the event of a fire. With their commitment to safety and sustainability, e.systeme21 and Q3 Energie are setting new standards in the industry and underlining their commitment to acting responsibly.
Jörg Steimann, e.systeme21GmbH
Fireman's switch safety for PV systems: Why actually?
The inverter is usually installed centrally in the building near the domestic power distribution. This can be switched off, as can all the electricity in the house. What cannot be switched off is the voltage coming from the modules: up to 1,000 volts of direct current remain in the building. Please note: from 120 V direct current, this is considered life-threatening.
This applies not only to the fire department in the event of a fire, according to their "Recommendation for action on photovoltaics", a minimum distance of up to 5 meters (depending on whether spraying or extinguishing jet) must be maintained from live parts, but also to maintenance and cleaning work, etc. Self-protection takes precedence over external protection.
Therefore, the unanimous wish is for a safe disconnection device for photovoltaic modules in order to be able to completely de-energize the building in the event of a fire, including the DC side.
Fireman's switch safety: Press releases on our fireman's switch for PV systems
Fireman's switch safety: Press releases on our fireman's switch for PV systems
Fireman's switch safety: Special features of the QFire fireman's switch for PV systems
The Q3 QFire fire switches for PV systems are certified to IEC 60947-3 and are planned to customer specifications and built by us in Kaufbeuren - Made in Germany. The fireman's switches are customized according to the number of strings (up to 16 per box), integrated overvoltage protection if required (here we install T1+2 as standard, but can install any other desired type) and also integrate fuses in/and positive and negative poles on request.
You have the choice between connector or terminal technology (MC4-Evo 2 from Stäubli as standard), type of housing (some applications require metal housings)... We combine all elements of the connection technology and can therefore also offer string reductions (8 inputs, 4 outputs, for example).