(Update January 9, 2018) Many customers ask us whether their inverter supports Modbus and where exactly they can check this. Our product management has prepared a detailed list about this topic.
You can find it here:

1. Go to the SMA download page for the Modbus protocol interface

Download the Modbus specification (ZIP file) there.


Technical Information_Modbus2

Please note that you may see a different version number if the document has been updated since this was published.

2. After you extract the ZIP file, you will find two files.


You can find all the devices that support Modbus in the device-specific list (Excel), under “SMA Device Types.”

SMA Device Types
Sunny Boy                                                                                         ID
SB 5000SE-10 9225
SB 3600SE-10 9226
SB 3000TL-21 9074
SB 3600TL-21 9165
SB 4000TL-21 9075
SB 5000TL-21 9076
SB 2500TLST-21 9184
SB 3000TLST-21 9185
SB 3500TL-JP-22 9162
SB 4500TL-JP-22 9164
SB 3000TL-US-22 9198
SB 3800TL-US-22 9199
SB 4000TL-US-22 9200
SB 5000TL-US-22 9201
SB 6000TL-US-22 9274
SB 7000TL-US-22 9275
SB 7700TL-US-22 9293
SB1.5-1VL-40 9301
SB2.5-1VL-40 9302
SB3.0-1SP-US-40 9328
SB3.8-1SP-US-40 9329
SB5.0-1SP-US-40 9304
SB6.0-1SP-US-40 9305
SB7.0-1SP-US-40 9330
SB7.7-1SP-US-40 9306
SB3.0-1AV-40 9319
SB3.6-1AV-40 9320
SB4.0-1AV-40 9321
SB5.0-1AV-40 9322
Sunny Boy Storage
SBS2.5-1VL-40 9326
Sunny Tripower
STP 8000TL-10 9101
STP 10000TL-10 9067
STP 12000TL-10 9068
STP 15000TL-10 9069
STP 17000TL-10 9070
STP 15000TLEE-10 9182
STP 20000TLEE-10 9181
STP 10000TLEE-JP-10 9222
STP 12000TL-US-10 9194
STP 15000TL-US-10 9195
STP 20000TL-US-10 9196
STP 24000TL-US-10 9197
STP 30000TL-US-10 9310
STP 20000TLEE-JP-11 9271
STP 10000TLEE-JP-11 9272
STP 5000TL-20 9098
STP 6000TL-20 9099
STP 7000TL-20 9100
STP 8000TL-20 9103
STP 9000TL-20 9102
STP 10000TL-20 9281
STP 11000TL-20 9282
STP 12000TL-20 9283
STP 15000TL-30 9336
STP 20000TL-30 9284
STP 25000TL-30 9285
STP 25000TL-JP-30 9311
STP 50-40 9338
STP 50-US-40 9339
STP 50-JP-40 9340
Sunny Island
SI3.0M-11 9278
SI4.4M-11 9279
SI6.0H-11 9223
SI8.0H-11 9224
SI4.4M-12 9332
SI6.0H-12 9333
SI8.0H-12 9334
3. If you require further information, please click on an individual tab.

You will find the relevant details about the device types and firmware that are supported there.


Do you have any further suggestions for the Modbus interface? Please feel free to add them to the comments section.

Please find more information about Modbus on our website SMA Developer.

5.00 avg. rating (97% score) - 2 votes

In a previous blog, we discussed some good reasons to oversize your PV array. In this blog we will discuss how, by oversizing your inverter, you can correct a site’s poor power factor.

Electricity used in our homes and businesses is (almost always) alternating current. Put simply, voltage and current that are transmitted throughout the electric power grid in a sinusoidal waveform averaging 0. When these current and voltage waveforms are perfectly synchronised in time, they have a power factor of 1 or pure active power.

Example of pure active power (left) with current and voltage perfectly in-phase, and of pure reactive power (right) with current and voltage perfectly out-of-phase.

Example of pure active power (left) with current and voltage perfectly in-phase, and of pure reactive power (right) with current and voltage perfectly out-of-phase.

When we consume electricity (in pumps, fridges, lights, etc) current and voltage waveforms can  go out of alignment. This will lead to a power factor ≠ 1. As a site’s power factor moves further away from 1, they will typically incur increased grid quality supply charges from their electricity provider. This is where your SMA inverter can begin to help save you even more money. By utilising SMA inverter’s built in grid support functionality, you can correct a bad power factor by feeding reactive power as well as active power and hence reduce the grid quality charge component of your electricity bill. This can often be cheaper than using additional power factor correction equipment such a capacitor banks.  Often active power  is just as valuable to a site as reactive power for correcting power factor. This creates a financial driver to oversize your inverter.

How much should I oversize my inverter?

Since this is an abstract concept for a lot of system designers and installers, let’s work through an example.

First, we need to understand the relationship between ACTIVE, REACTIVE and APPARENT power. Apparent power consist of active and reactive power, two different types of power existing only in its pure nature. Because active and reactive power don’t have a relationship, it is impossible to convert one power type to the other. A graphical model of such relationship is a cartesian coordinate system with active power for the x-axis and reactive power in the y-axis. These 3 power types are related together according to Pythagoras’ theorem as shown in the following diagram.

Relationship between Apparent, Active and Reactive power.

Relationship between Apparent, Active and Reactive power.

Now let’s assume we have a site which is consuming 80kW of active power with a site power factor of 0.85 due to some inductive loads such as pumps and motors. This would result in the following relationship:

Power consumption without power factor correction or generation

Power consumption without power factor correction or generation

Now let’s assume the site needs to correct its power factor back to 0.90, and they also want to reduce their active power consumption by ~60%. If we begin with a 60kW solar system (60kW PV array, 60kW inverter), and this system generated power with a cos(φ) of 1.0, we would have the following power consumption. We can see that if we did nothing to the way the solar system operated, it could actually make the site’s power factor (and hence power quality charges) significantly worse from the utility’s point of view.

Power consumption with Generation at cos(φ) 1.0

Power consumption with Generation at cosphi 1.0

Now let’s operate the solar system with a cos (φ) of 0.82 to try and correct the site’s power factor. We would have the following power consumption and generation relationships:

Power consumption with generation at cosphi 0.82

Power consumption with generation at cosphi 0.82

This would then have the resultant power consumption for the site according to the following:

Resultant power consumption with inverters correcting power factor

Resultant power consumption with inverters correcting power factor

We could then consider to implement a cos(φ) function similar to the following could help to ensure that as the solar system increases its output power, it will change its cos(φ) to compensate for site power factor.

Dynamic cosphi function to assist correcting a poor site power factor

Dynamic cosphi function to assist correcting a poor site power factor

In this example, we require 60kVA of inverter capacity, but only 49kW of active power generation, meaning we can oversize our inverters by about 20% compared to the size of our PV array. SMA inverters can generate reactive power without using any active power. Within SMA, were refer to this capability as Q @ Night ( read more about Q @ Night here ).



By oversizing inverters, you have reserve reactive power capacity which can be utilised without sacrificing active power generation. Utilising the built-in grid support functionality in SMA inverters, such as a dynamic cos(φ) function, can help to improve a site’s power factor and in turn help to reduce grid quality supply charges a customer might incur from their electricity provider.

You can read more about this topic in detail by reading SMA’s PV Grid Integration technical compendium.

0.00 avg. rating (0% score) - 0 votes

Country wide solar adoption depends upon growth in awareness and involving the common man. Understanding this, the Government of India has focused on rooftop solar development while taking enormous leaps in utility scale solar installations. It is important to note that India has a rooftop solar energy generation potential of 124 GW (current total energy generation 330 GW). And even if only 1.3% of India’s total households (total 248,408,494) are solarized with rooftop technology, more than 30% of that estimated energy capacity can be harnessed.

And with solar tariffs standing at record low INR 2.44 /Kw (lower than conventional energy tariff), this presents an incredible opportunity for the country to quickly grow their rooftop capacities. Let us list the viability that rooftop solar brings to the table to validate the importance of rapid rooftop solarisation within India.

Feasibility of Rooftop Solar Plants

Although, India’s utility scale solar installations can add humongous amount of solar capacities at one go (e.g- 648 MW capacity plant at Kamuthi, Tamil Nadu), they require huge spread of land, which by the way India doesn’t have, considering the increasing population (1.34 bn in 2017). Additionally, utility solar installations require well developed infrastructure to connect the harvested energy to the grid. On the other hand, when we are talking about rooftop solar installations, the cost of land and required infrastructure seems to be only a fraction of the utility scale solar installations.

In the same breath, we need to point out that long life span of solar modules (27 years avg.) and low maintenance requirement of solar technology actually helps rooftop solar users to get benefits of green energy for decades without burning a hole in their wallets.

It is true that utility based installations are now leading Indian solar sector. But, it is the future of rooftop solar that can offer faster solarisation of a country, while reducing the electricity bills of the consumer (consumers pays less to utility), and allowing them to produce and even sell energy.

With Net-metering schemes (which 36 states and UTs have identified and in different stage of implementation), consumers can sell the excess energy to the grid, becoming energy reliant. And when each household becomes energy reliant, India vision of energy security will definitely get realized.

Understanding the potential, Government of India has mandated solar installations in PSUs/institutions, and new Government building in many states. Brought in new investment opportunities (setting up US$1.5 billion fund for grid connected rooftop installation by SBI, IREDA, PNB and World Bank). Offering 30% capital subsidy to residential and not-for-profit institutional investors. And all this effort has resulted in ~1.7 GW rooftop solar capacity. However, challenges still remain.

The Challenges

India has reached ~1.7 GW rooftop solar capacity within a short time span. However, the proposed target of 40 GW by 2022 is still far away and would require a faster adoption framework.

Although Government is providing subsidies to encourage rooftop solar installations, the financial support is only available after commissioning of the plant. Therefore, it befalls upon the consumer to bear the initial investment. Besides, there are some discrepancies and delays in getting the subsidies after commissioning a plant, which only creates problems for the consumer.

It is a fact that Indian Government is actively focusing on generating fund for rooftop growth. But, to reach more than 95% of the remaining targeted capacity (40 GW) within next 5 years, the fund generation has to be boosted.

Also with states of India coming up with their own rooftop policies (maintaining the central guidelines) it has become challenging to evaluate and compare the state wise rooftop solar growth in India.

Net-metering also doesn’t have required clarity on implementation models. And requirement for multiple permissions, lack of awareness within the utility stuff and the consumers is creating a huge challenge to meet installation targets.

In regards of consumer awareness, India needs to disclose information about cost, benefits, and important information to go solar. Campaigns are being organized by National Solar Energy Federation of India (NSEFI) and MNRE to raise awareness, but more is needed to reach the set target.

Lastly, clarity on policies is needed. It will explain the functionality of the policies and help consumers and developers to go for rooftop installations.

Way Forward

Offering easy financing options, faster delivery of subsidies, setting up a larger fund for rooftop, bringing in a uniform rooftop policy and mandating states to follow for easier evaluation, offering information through television, radio and other media platforms, will help India realize its full rooftop solar potential.

Involving common men in the fold is the fastest way to solarize the country, and rooftop solar brings that opportunity to us. This is the right time to enhance and expand the solar sector, when the demand, innovation, and investment on solar is high. So, India should utilize this opportunity and focus on country wide rooftop solar installations to become the green energy super power it aspires to be.

Please follow and like us on social media:

Government and private players working in a unison has created a favourable environment for solar in India. The growth has been incredible till date, showing considerable increase in energy generation rate (India is estimated to become energy surplus country at the end of 2017). Solar favouring policies, strategies, and systems in place have done a great job in leading India to become the third largest solar market and 4th largest economy in the world.

And although, major cities of India have received attention in energy improvement (through solar installations), rural areas in India are still under the shroud of darkness. Fact shows that Government of India has taken initiatives like- Power for all, Saubhagya plan, and Deendayal Upadhyaya Gram Jyoti Yojana (DDUGJY) to electrify villages. But it is important to note that more than 3000 villages are still un-electrified. Issues concerning reaching the electricity lines to rural areas, and huge distribution losses (~30%) have made it harder to illuminate the rural areas. In such a scenario, it is important to highlight that a 50 kW solar grid with distribution capacity of 5 KM can power ~500 homes, businesses, schools, and couple of telecom towers with ease.

Therefore, it is only logical that the Government should consider using solar powered mini-grids to the needy areas for rapid electrification, awareness, and energy sustainability.

Mini Grids Are Gaining Popularity

Although, the rural electrification process is progressing (13,97,57,084 households electrified), it is to be noted that just having access to electricity doesn’t necessarily offer energy sustainability. Many of the villages that are already registered as ‘electrified’, have only 10% of their public places and households electrified. And in some instances, electrified villages only received electricity for 5-6 hours a day.  Such a scenario calls for a better energy framework utilization (Solar Mini-grid). And solar installations within villages are gaining popularity, as they promise to offer energy sustainability. Government has taken the hint and taking action on establishing solar mini-grid plants.

Mini grid installations in Chhattisgarh by CREDA and in Sunderbans (WB) supervised by WBREDA have already shown the capability to light up the un-electrified villages. Establishing a Mini-grid circle has brought electricity to 130 households in villages like Kasina and Bheldi (in Bihar). And following the footprint, Jharkhand Renewable Energy Development Agency (JREDA) has introduced a project to electrify 320 households across 11 villages with the help of Mini and Micro grids. Government of India also has plans to establish 70 grids in Bihar and UP to offer energy. Supporting the initiative, UP Government is planning to offer 30% subsidy on these installations. Research shows that such developments have led to 16% off-grid development target.

However, as the country focuses on 100% electrification within 2019, more effort on establishing mini-grid is needed to achieve the target.


Policy: Material procurement laws, delays in land acquisition, lack of awareness, and the gap between creation and implementation of policies- are slowing down solar Mini-grid’s growth. India desperately needs a regulatory framework to support and aid these processes in the villages. More awareness is needed to help the people in the village understand the cost, the profit and the benefits of choosing SPV mini-grid over diesel power energy solutions. Encouraging private entities to deploy isolated Mini-grids in villages is also needed. Last but not the least, a focus on making subsidy disbursal rules more flexible is needed to encourage private developers.

Economic: Mainstream economy is mainly focused on utility based solar installations. Therefore, lack of financing options have isolated Mini-grid developers and brought the question whether their ventures will turn profit or not. Lack of profitable off-take agreements, and debt financing facilities discourage the developers from venturing into rural solar electrification. Likewise, lack of subsidies on energy storages has made solar growth challenging.

Technological: Delays or lack of net-metering deployment ratio, lack of or no standard responses framework to system abuse, confusions in tariff collection are few of the technological issues that halt Mini-grid progress.

More Focus in Needed for Faster Solarisation

Solar Mini-grids promise to offer energy solutions similar to standard grid based energy, however with solar mini-grid, there will be no electricity outages. Besides, with solar panel cost and tariff declining, it would be a feasible option for people in the villages than shelling out money for diesel or kerosene for energy. Therefore, solar mini-grids are best option to illuminate the rural parts of India, and create awareness within common people to adopt solar.

However, to make mini-grids more effective, some changes need to be made in the existing renewable energy structure. A clear policy development and implementation can certainly help. Nevertheless, the success lies within collaborative work between the Government and private entities.

Please follow and like us on social media:




SolarQuarter Tweets

Follow Us For Latest Tweets

SolarQuarter 100 CXOs Confirmed To Attend Solar CEOs Meet & RE Sundowner 2018_17 Sep 2018, New Delhi, Radisson Blu Plaza, Aeroci… https://t.co/NmytYpREMp
Friday, 14 September 2018 08:09
SolarQuarter EV Investment & Finance Summit Is Here_Book Your Seats Today_1 Nov 2018, Mumbai - https://t.co/4I4pOy8M5j
Wednesday, 12 September 2018 05:07
SolarQuarter Hey << Test First Name >>, Here's Your Event Photo Gallery, Checkout The Amazing Moments - https://t.co/qE0yhHY7w0
Wednesday, 05 September 2018 13:08