Frequently asked questions

Sensors & detection

How does magnetic detection work ?

Magnetic detection works by measuring the variation in the Earth’s magnetic field. Vehicle detection is based on an algorithme which uses detection thresholds and high and low frequency filters.

What can interfere with the functioning of the magnetic sensors ?

External conditions (running water, subways, buses, trams, rail lines, ...) can interfere temporarily with measurements made by sensors. Our patented hybrid “magnetic nanoradar” sensors reduce the adverse effects of these disturbances by using additional detection technology.

Where is the senior situated in the parking space ?

Detection errors can occur depending on the position of the vehicle in the parking space. This can be referred to as an “equal arm scale” effect. The vehicle’s metallic mass is perfectly contained within the sensor’s “magnetic bubble”. The sensor does not detect the vehicle’s presence, in the same way that a scale with 1kg on each platform will indicate zero.
Consequently, the sensors are installed asymmetrically, at around 1.80m from the back of the parking space to avoid this problem.

Is a vehicle parked across two spaces detected ?

Yes, both spaces will be shown as occupied in software and accounted for on their connected display panels.

Are motorbikes and similar two-wheeled vehicles detected ?

Yes, in general they are detected if they are parked near a sensor.

What is the replacement kit ?

It is made up of a set of replacement sensors, a specific lever key and a NFC badge which is required to activate the sensors. As a result, you can carry out simple maintenance in the case of defective sensors.


Is the 3G network’s performance reliable ?

Yes, the 3G/3G+ mobile network is reliable. It is currently the most wide-ranging network in France, covering 90% of the country. This network has a throughput of 2 to 42 Mb/s, with a theoretical average flow of 14.4 Mb/s. Furthermore, the various network providers indicate a mobile availability rate of 99.5% for the data network.

Via which mobile network provider do you use for data transmission ?

Any of them. Our hubs are equipped with M2M SIM cards. We select the provider with the best network coverage for the specific sites we deploy for our clients.

What is M2M ?

The concept of « machine to machine communication» associates information and communication technologies with “smart” communication objects, in order to allow such objects and information systems to interact with each other, without human intervention.

This technology works via networks, public mobile networks in particular (such as GPRS or UMTS), or via short distance wireless networks like Wi-Fi, bluetooth or RFID. Another method is to connect devices in a local loop, itself connected to a data hub which acts a gateway to central databases or the Cloud.

The innovation behind our Smart City and Smart Grid solutions mainly use M2M technology.

How well does the 868MHz frequency perform ?

This frequency belongs to the hyper frequency or microwave category.
It is stronger and penetrates better than WiFi (2.4 GHz) or Bluetooth (2.1 GHz), particularly in the presence of water, snow or leaves.

Can anything interfere or disrupt radio-wave transmission ?

No, due to our peer-to-peer network communication architecture.

What are the advantages of a peer-to-peer architecture ?

Energy consumption is significantly less than grid networks such as Mesh.

A sensors only uses energy to transfer information about its availability. It is not aware of the status of neighboring spaces. Additionally, a defective sensor has no incidence on the other sensors within a peer-to-peer network.

Photovoltaic solar panels & new energy sources

What makes a photovoltaic installation ecological ?

Solar panels produce renewable energy which respects the environment. They can be recycled. Energy is produced close to consumers, thus reducing supply-related consumption.

Can a lightening strike damage the photovoltaic solar panels ?

Solar panels do not attract lightening. A converter counters over-voltage that could be caused by lightening. However, should lightening strike, photovoltaic installations could be dammaged or even destroyed. In that case, multi-risk insurance policies cover the damages incurred.

Can solar panels help to obtain the HQE (High Quality Environment) label ?

A photovoltaic installation meets the criteria to obtain the HQE label as it uses local renewable energy and reduces energy consumption pollution.

Do solar panels emit carbon dioxide ?

Solar panels do not emit carbon dioxide when they produce energy. Electricity is used only during the production of the panels.

According to the French Agency for Environment and Energy Management, (l'Agence de l'environnement et de la maîtrise de l'énergie (Ademe)) and the Hepsul association, it takes 3 years for a solar panel to compensate for the carbon dioxide emitted for its production.

Can solar panels be recycled ?

The majority of a solar panel’s components can be recycled. The photovoltaic modules are designed to be 85% recyclable. To date, the first generation of solar panels have not reached the end of their life. That should be in around 10 years. The lifecycle (ACV) of all kinds of photovoltaic installations are currently being studied, as are thermal solar systems.

At the end of their life, solar panels can be used again to produce new solar panels. Silicon is the base material for solar panels and it is recycled to make new panels. So is the aluminium frame.

The remaining glass following the recycling process is used to make fibre glass, insulation and glass packaging products. Metals and plastic materials are reused as raw material.

The association PV Cycle, founded in 2007, has created a photovoltaic panel recycling chain. (//

How long do solar panels last ?

SERELIO’s photovoltaic solar panels are guaranteed for 20 years and can last up to 30 years. Decline in output is low: panels maintain 90% of their power after 10 years and 80% after 20 years. The easy operation of the panels and their lack of moving parks limit wear and tear. As a result reliable estimates of their average length of life can be made. The only delicate component of photovoltaic panels is the converter which is used to convert the direct current produced by the panels into an alternating current. They generally last between 8 and 12 years. As it is a key component of the system, it is preferable to use a high performance converter.


For several years now, all those involved in creating photovoltaic energy have made considerble efforts to increase the recycling options for solar panels. Currently it is easy to recycle: most of the components are recoverd and recycled following thermal treatment. This applies to the more easily recyclable elements of photovoltaic solar panels (glass, metals).

Clear progress has been made in recent years to recover and recycle traces of silicon, lead and cadmium. Photovoltaic cells are chemically treated and go through a process of purification. The silicon, lead and cadmium are then recovered and used again for the production of new photovoltaic cells.

Are solar panels storm resistant ?

The solar panels meet IEC standards. This certification guarantees quality in terms of mechanical stability and respect for electrical parameters.

To meet these standards, panels are tested by blasting balls of ice (from 0.75cm to 1.25cm in diameter) at a speed of 140 km/h. They are protected against bad weather conditions such as hail and snow.

Compared to other renewable energy sources, what are the advantages of photovoltaic energy ?

Photovoltaic energy can be used everywhere as most of the world has sunshine every day and as a result, an investment in photovoltaic energy is financially sound and ecological. Photovoltaic systems are fully adaptable and the size of installations can be easily adjusted depending on your needs or budget.

Photovoltaic energy is renewable: no movement, no direct or indirect pollution, no waste nor incidence on the surrounding environment. Furthermore, solar panels do not release any CO² into the atmosphere.

Where do your panels come from ?

The solar panels produced by SERELIO have been made in Germany and Argentina for nearly 25 years. The panels have high quality performance.

Popular beliefs around photovoltaic energy

« Solar panels only produce solar energy when it’s sunny and warm. »

FALSE. Photovoltaic installations function in all seasons, whatever the weather conditions, as long as they are in daylight. Even if energy production is higher in direct sunlight, solar panels continue to produce energy when it’s raining or overcast.

« Photovoltaic technology is too recent to be reliable. »

FALSE. The press often states that the photovoltaic industry is very recent in France and that it lacks the hindsight to be able to guarantee solar panel quality and productivity. However, French industry has been producing solar panels for 25 years in fact! The life cycle of solar panels has been extensively studied and can currently reach up to 35 years. A solar panel recycling chain has been set up and is fully operational.

« The use of solar electricity combats global warming. ? »

TRUE. One of the major problems caused by the use of fossil fuels is the emission of greenhouse gases (CO²). An increased number of photovoltaic installations in France will reduce the need to produce electricity from polluting sources. Deciding to produce renewable energy is not only environmentally friendly but also profitable !

« Solar panels only produce solar energy when it’s sunny and warm. »

FALSE. Photovoltaic installations function in all seasons, whatever the weather conditions, as long as they are in daylight. Even if energy production is higher in direct sunlight, solar panels continue to produce energy when it’s raining or overcast.

« Solar panels are fragile and can be easily damaged and broken. »

FALSE. The panel’s solar collectors are made out of borosilicate glass. This material does not heat up and can withstand shock and extreme weather conditions such as hail and storms. Solar panels can bear all kinds of strain and hardship.

« Solar panels require regular and tedious maintenance. »

FALSE. Solar panels are cleaned naturally by the rain and require no particular maintenance. In dry regions, a hose can be used to rinse the panels. They only require cleaning once a year.


What glue is used to attach the sensors? Is it long-lasting and resilient ?

We recommend “Plastiroc” cold coating for road markings made by AXIMUM.

Protects the user's health and safety: non-harmful, non-irritant, non-inflammable product.
NF environment ecolabel guaranteeing low environmental impact.
Excellent mechanical resistance: including heavy traffic.

How are the sensors installed ?

An electric coring system with a diamond cutter such as TYROLIT is required. Once the coring is completed, the base can be sealed using “Plastiroc” cold coating.

What are the prerequisites for the installation of the sensors ?
  • Ground marking finished if in construction or renovation
  • Coating must be dry
  • Favorable weather conditions, if installation is outdoors
  • Installation during the day is preferable
  • Parking spaces need to be available if installation is carried out during the day or during opening hours
How long does the installation phase last ?

Our wireless solution is installed quickly and allows us to be flexible in our interactions with all those involved in large scale operations.
Cold coating only takes 30 minutes to dry.
Metics: 300 sensors installed in one day by a 4-person team.
In 3 days: 450 sensors installed + 20 solar totem poles set up + configuration & implementation