Fronius Launches Smart Meter for Feed-In Management

The Fronius Smart Meter measures the electricity consumption of a building and communicates in real time with the inverter, which then controls the system’s output power to keep the electricity fed into the grid at or below the feed-in limit.

An increasing number of grid operators set feed-in limits for grid-connected solar systems. The global smart meters market is estimated to grow from an expected $11.1 billion in 2014 to $18.2 billion by 2019, at a CAGR of 10.2 percent from 2014 to 2019, according to a study by MarketsandMarkets.

Thanks to high accuracy and fast communication via Modbus RTU, the Fronius Smart Meter is suitable for various dynamic feed-in management applications. “We are excited to offer a simple and cost-effective solution for self-consumption systems that require dynamic feed-in management. This will help to further increase solar penetration in our electrical grid”, says Tristan Kreager, Director of Solar Energy at Fronius USA, based in Portage, Indiana. The product will begin shipping immediately.

In conjunction with Fronius Solar.web, the Fronius Smart Meter offers a detailed overview of energy flows within a home or business. In addition to the solar production data, customers get a detailed visualization of their energy consumption and can optimize their energy usage based on the individual load curve. This gives installers the opportunity to design tailored energy solutions to home- or business-owners and to up-sell to them in the future. “For installers, Fronius Solar.web is a lead database for future sales and we can help our installers to grow their business,” Kreager explains.

The Fronius Smart Meter is compatible with all Fronius inverters with an integrated Fronius Datamanager 2.0 (RS485 interface for Modbus RTU), which is included in Fronius Galvo and Fronius Primo inverters. The Fronius Datamanager 2.0 can also be added to any Fronius Symo, Fronius IG, IG Plus and IG Plus A inverter.

Maintenance for INMESOL Generator Sets

Maintenance for Generator Sets

To ensure the correct operation of the generator sets and to prolong their service life, it is essential to carry out adequate maintenance specific to each of the systems in the equipment: mechanical motor, alternator, chassis, fuel tank, battery and control panel.

Maintenance should be performed on a regular basis and requires training, as well as specific tools and knowledge. Consequently, it should be done by qualified personnel with a sound knowledge of and respect for safety rules.

Likewise, the type of motor in each generator set – brand, model, function, power and whether it uses petro or diesel – and the environmental conditions determine the specific needs and maintenance protocols.

Types of Revisions

For all the generator sets – except the emergency sets, which require special maintenance – there are 3 types of revisions: sporadic, regular and extraordinary.

Sporadic revisions

This is a basic check, which is very simple to perform and can be done by the generator set user. It consists of starting up the equipment in accordance with the instructions provided by the manufacturer. It should be carried out on a regular basis and takes a few minutes.

Regular and extraordinary revisions

The regular revisions should be carried out by suitably trained technicians (at Inmesol we facilitate this training to our clients) and the extraordinary maintenance is performed exclusively by qualified personnel from the Inmesol Technical Assistance Network.

Maintenance for Emergency Equipment

Given that the function of this type of generator set is to operate exclusively when there is a failure in the electricity supply network, it is important to change the following at least once a year:

  • The oil
  • The oil filter
  • The diesel filter
  • The diesel pre-filter, if there is one.

Motor Maintenance

Just like vehicle engines, the motors in generator sets have combustion chambers, pistons and different auxiliary systems: the cooling system (radiators and ventilators), the filtration system (air, oil and fuel), and the electrical system (responsible for turning the equipment on and off).

In the filtration system, the air, oil and fuel filters, as well as the fuel itself, must be replaced after a determined number of service hours. This is normally required once a year, but the timeframe varies according to the manufacturer and other factors. For example, in the case of the air filters, the replacement frequency depends on the concentration of dust particles in the environment surrounding the generator set. It is also important to remember that the motor must be cold before carrying out maintenance on the fuel filter to prevent the risk of fire.

For the electric system, the battery power must be checked regularly and the electrolyte level must be tuned, adding distilled water to compensate for inevitable evaporation. To verify the density of the acid solution, the technicians use a densimeter.

Inmesol works with various brands of motors. Each manufacturer details the particularities of their models and the corresponding specific recommendations in a Service and Maintenance Manual. Technicians should always have this to hand when they perform maintenance services and pay close attention to the recommendations.

Understanding Ratings for Surge Protection Devices

Selecting the appropriate Surge Protective Devices (SPD) can seem like a daunting task with all of the different types on the market today. The surge rating or kA rating of an SPD is one of the most misunderstood ratings. Customers commonly ask for an SPD to protect their 200A panel and there is a tendency to think that the larger the panel, the larger the kA device rating needs to be for protection As we will explore in this paper, this is a common misunderstanding.

When a surge enters a panel, it does not care or know the size of the panel. So how do you know if you should use a 50kA, 100kA or 200kA SPD? Realistically, the largest surge that can enter a building’s wiring is 10kA, as explained in the IEEE C62.41 standard. So why would you ever need an SPD rated for 200kA? Simply stated – for longevity. So one may think: if 200kA is good, then 600kA must be three times better, right? Not necessarily.

At some point, the rating diminishes its return, only adding extra cost and no substantial benefit. Since most SPDs on the market use a metal oxide varistor (MOV) as the main limiting device, we can explore how/why higher kA ratings are achieved. If an MOV is rated for 10kA and sees a 10kA surge, it would use 100% of its capacity. This can be viewed somewhat like a gas tank, where the surge will degrade the MOV a little bit (no longer is it 100%
full). Now if the SPD has two 10kA MOVs in parallel, it would be rated for 20kA. Theoretically, the MOVs will evenly split the 10kA surge, so each would take 5kA. In this case, each MOV have only used 50% of their capacity which degrades the MOV much less (leaving more left in the tank for future surges).