Indesit Company (a leading European appliance manufacturer) in cooperation with Renesas Electronics Corporation has developed an innovative low cost networking technology named “Power Modulation” (PM), based on a new generation of smart plugs. This solution is freely available to all other manufacturers of household appliances through a new generation of 32 bit microcontrollers (Renesas RX210 family) dedicated to "smart appliances". PM communication is managed by a specific peripheral (PMI, Power Modulation Interface) of Renesas RX210 microcontrollers.

1. A new generation of smart plugs to add free connectivity
to household appliances
Valerio Aisa1
1
Scientific Advisory, Indesit Company Spa, Via Lamberto Corsi 55, Fabriano (AN), 60044, Italy
(Contact: valerio.aisa@consultants.indesit.com / valerio.aisa@gmail.com)
Abstract The willingness to transform the Energy System into an “enabled smart grid” means a clear change in the
role of major appliances, which must change from being “stand alone” offline tools to real “online networked smart devic-
es”. This improvement in technology requires the appliance to be capable of communicating with the electrical meters for
a more convenient management of the power consumption as well as their transformation into “sensors” to offer elderly
people living alone the possibility to use them for assistance and help. To make those changes real we have to solve some
technical issues related, for example, to the networking technology. These issues are limiting the quick development of the
new phase. For this reason, Indesit Company (a leading European appliance manufacturer) in cooperation with Renesas
Electronics Corporation has developed an innovative low cost networking technology named “Power Modulation”, based
on a new generation of smart plugs. This solution is freely available to all other manufacturers.
Keywords smart appliances, smart grids, smart plugs, smart sockets, smart adapters, energy management, ambi-
ent assisted living, internet of things, low-cost connectivity, power modulation, home automation, application pro-
files, communication standards.
tion to transmission, from distribution to sale, to accumula-
1. Introduction tion and, above all, to the smart consumption of energy.
This valuable link between ICT and the world of energy is
There are two important worldwide trends that drive the commonly identified with the term Smart Grid. Therefore,
development of connectivity in the home: the evolution of within the concept of Smart Grid there is the need to collect
the electric grid for improving efficiency, known as "smart and process in real time information generated by appropri-
grid revolution", and the need to stimulate the use of tele- ate measuring devices and sensors, distributed on the net-
medicine technologies for assisting elderly at home in order work in order to achieve a coordinated control of different
to improve their wellness and independency and at the same parts.
time to reduce social costs. Both of these require the col- There is also the need to encourage a more active role of
laboration of "smart objects", in particular smart appliances, the end users in the industrial sector and especially in the
which are able to communicate. The necessary communica- residential sector, aimed at stimulating - through appropri-
tion infrastructure, mainly based on radiofrequency, can be ate levers of economic convenience - a more careful and
the same for both situations (Figure 1). The present paper collaborative participation in the management of energy
shows how household appliances can work both as energy consumption to reduce peaks through the leveling of power
saving devices and as "vitality sensors" for the elderly, absorption profiles [1]. In both cases the creation of ade-
thanks to a breakthrough communication technology that is quate communication infrastructures [2,7] associated with
based on a new generation of smart plugs and which doesn't the distribution network is thus essential.
influence the cost of the appliances.
1.2. Ambient Assisted Living and smart appliances.
1.1. Smart grids and Smart appliances.
The average lifetime of the population is increasing eve-
The growing demand for energy and the absolute need to rywhere, thanks to the achievements of medicine and the
reduce climate impact in the world is producing a strong work to prevent disease that most countries have been pur-
convergence of scientific, industrial and political interests suing for some time. This fact is positive but, nevertheless,
towards the use of information and communication tech- causes an aging population of the planet and generates so-
nologies (ICT) to support the process of structural trans- cial costs, with the consequent need, for the governments of
formation of each phase of the energy cycle: from genera- most developed countries, to create the necessary condi-

2. tions for citizens to keep their autonomy and independence reducing healthcare costs.
in their own homes for as long as possible, at the same time
Figure 1. Main drivers to add connectivity to household appliances.
One of the most effective ways to meet these needs is by technology into the control systems of household appliances,
encouraging the use of telemedicine to assist the elderly in with the aim of giving the products a greater versatility and
their homes, aimed at maintaining a high quality of life and "intelligence".
drastically reducing the need for hospitalization.
The research activities of Indesit Company highlighted 2.1. Birth of Margherita DialogicTM (1995).
how household appliances (which are able to communicate) The aforementioned commitment began to show the first
can play the role of "sensors of the vitality" of the user results in the second half of the '80s, with the first digital
(Figure 1), able to monitor his/her daily interactions with products for cooking and refrigeration, but found its full re-
the appliances - the opening of the doors of the refrigerator, alization in the '90s, when Vittorio Merloni decided to
for instance - to infer his/her habits and report any unusual launch the ambitious project - at that time really very inno-
behavior that might occur in connection with situations of vative for the white goods industry - to acquire all the skills
hardship or danger for the user. necessary for autonomously developing digital control sys-
tems for its products.
From this project Margherita Dialogic (1995) was born,
2. Indesit's past experience in smart ap- the first digital washing machine capable of communicating
pliances with the surrounding environment, and then (1997) the be-
ginning of Indesit relationship with Enel, the big Italian
Indesit addressed connectivity for the first time about 25
utility, aimed at optimizing the energy consumption of the
years ago, when President Vittorio Merloni conceived
home through the dialogue of the household appliances
ArisionTM, the "digital butler" able to speak and control the
with the new digital electricity meter (under development at
home, born in 1985 in Merloni Elettrodomestici (Indesit
that time).
Company since 2005). It was the first device able to enter
into a relationship with the household by using voice mes-
sages.
The experience of Arision was a strong stimulus for the
future commitment of the Company in introducing digital

3. 2.2. Ariston DigitalTM and Leon@rdoTM (1999). didn't buy the product but just its service -, the Company
1
The interaction with Enel, Echelon and the Massachu- gained international credit and visibility.
setts Institute of Technology (MIT) of Boston allowed the
Company, under the strong commitment of Francesco Caio
(CEO, at that time) and President Vittorio Merloni, to de-
vise and implement Ariston Digital (1999), the first system
of household appliances (Figure 2) capable of communi-
cating (using LonTalk protocol) with each other and with
the outside world through Leon@rdo (Figure 3), the first
"Internet appliance" dedicated to the kitchen.
Figure 2. Ariston Digital, the first system of connected household
appliances (1999).
Figure 4. Margherita2000.com, the first washing machine controllable
through a cellular phone or a PC (1999).
2.4. Energy@home project (2009).
After this experience, Indesit was able to start playing an
active role in CECED [4] - the European organization of
manufacturers of home appliances - with the opportunity to
effectively contribute, along with Electrolux,
Bosch-Siemens, Whirlpool, Miele and other manufacturers
of white goods, to the development of common communi-
cation rules to ensure interoperability between products of
different brands [5,6].
It was a long standardization process which in recent
years has found its first important concretization with the
recent project named Energy@home [7] - sponsored by
Enel and developed in collaboration with Telecom Italia and
Electrolux - which officially started in October 2009 and
which will finish by the end of 2012.
The goal of this project is to define, develop and make
Figure 3. Leon@rdo, the first internet appliance for the kitchen (1999). available all the hardware and software components re-
quired to minimize the cost of electricity and reduce CO2
2.3. Margherita2000.comTM (1999) and Margherita emissions through an appropriate dialogue between the
Pay-per-Use TM (2002). household appliances and the digital energy meter, and to
open the home to the world of new web based services
Through the Ariston Digital experience - characterized
(Figure 5).
by the great success of Margherita2000.com (Paris, De-
The dialogue between the electric utility and the house-
cember 1999, see Figure 4), the first appliance capable of
hold appliances is based on a new device of Enel’s called
communicating with a mobile phone and of interacting with
Smart Info (SI), which has access via PLC (Power Line
the web, and then the success of Margherita Pay-per-Use
Communication) to all the data generated by the electricity
(2002), the first washing machine in leasing, where the user
meter and can benefit from a broadband internet connection
made available by Telecom Italia through its new Home
1
Echelon (Palo Alto, CA), leader in the field of data communication, was partner Gateway.
of Enel in the project for developing its new electricity meter.

4. Figure 5. Energy@home global architecture.
The local network HAN (Home Area Network) is based
on radio frequency and employs low power ZigBee tech-
nology [3]. The ZigBee based communication node, which 3. Problems for connecting white goods
is located within each element of the system (Smart Info,
Home Gateway, appliances, smart plugs, smart sockets...), The great pioneering effort made by Indesit in the mid
has a new "application profile", currently being developed 90s, appreciated also internationally [12, 13], could not be
by the four partners of the project. This new profile incor- finalized to the market for the following three main reasons:
porates the results of many years of work, aimed at ensuring  the total lack at that time of communication rules
interoperability between products of different brands, which shared by the various manufacturers of white goods,
was carried out by CECED during the first half of the pre-  the almost total absence in homes of broadband (In-
vious decade and recently standardized by CENELEC [5,6], ternet penetration in the home relates to recent years and is
and its purpose is to complement the preexisting profiles still in progress)
Smart Energy (SE) [8,9] and Home Automation (HA) [10]  and, last but not least, the excessive cost of the con-
of ZigBee protocol. It incorporates and extends the features nectivity.
of earlier SE and HA profiles in order to give to each ap- While the first two problems will be completely solved,
pliance the full potential that comes from its new role as an the third one remains a barrier to the spread of connectivity
"intelligent" element of a home automation system, and it is for mass products: although there will be, day by day, tech-
technically configured as an extension of the same "ZigBee nical solutions with more affordable costs (such as
Home Automation profile" (addition of appropriate new ZigBee-based communication nodes, for instance), never-
clusters to HA profile), expressing the results of many years theless the introduction of a communication node inside an
of experience on connectivity issues of European manufac- appliance still causes considerable "side effects".
turers of household appliances. 3.1. First problem: tying household appliances to a spe-
Indesit has recently joined the ZigBee Alliance [3] and is cific communication technology can be risky and expen-
making a great effort, supported by strategic alliances sive.
[11,27], towards the aim of reducing the time-to-market of
its "intelligent" products. A first obstacle comes just from the presence of a com-
munication node within a product, tying it to a specific

5. communication technology. This is risky, because it requires founded by Hitachi, Mitsubishi and NEC), creating a pe-
frequent updates to the product caused by the natural evolu- ripheral device for microcontrollers named PMI (Power
tion of the adopted protocol. In fact, the need to update the Modulation Interface). After the signing of a free license
product would be a great burden for the user, because it re- agreement (March 29th, 2010) between Indesit and Renesas,
quires the presence of specialized technicians, and it is very the Indesit PMI peripheral device has been added by
unusual for the white goods field. Renesas to a new family of 32 bit microcontrollers dedicat-
ed to smart appliances. In such a way, the low cost commu-
3.2. Second problem: household appliances with a nication technology of Indesit is now freely available,
communication node inside can be sold only through through Renesas RX210 microcontroller family3, or other
specific channels. similar microcontrollers4, to all manufacturers of electrical
A second problem is the cost of the communication node household appliances that want to use it.
which, placed inside a household appliance, increases its
industrial cost and decreases its competitiveness. This cost 3.5. Main features of PMI, a peripheral for microcon-
is increased also by the need to introduce mechanical trollers dedicated to smart appliances.
(hardware), electrical (extra wires) and electronic changes PMI (Power Modulation Interface) is an LSI that incor-
to install the communication node. As a consequence of this, porates PM technology to enable serial data communication
it is substantially impossible to sell products with a com- using the power supply cables of home appliances. When
munication node inside using traditional distribution chan- combined with a smart adapter (SA), or an interface be-
nels. tween home appliances equipped with the PMI module and
The use of a communication node on board may be use- house power wall outlets, the PMI provides a home net-
ful in the case of high-end products, where specialized dis- working system that connects various home appliances by
tribution channels are used. using general AC power lines used in a house.
Furthermore, the PMI peripheral device has three other
3.3. Third problem: too much time is needed to replace important functions: the Dynamic Demand Control (DDC)
all the household appliances already installed in the feature to support smart grid needs; a rigorous measurement
houses. of mains voltage (+/- 2%) to improve the performance of
A third problem, which concerns the "home system" and the appliance (capability to adapt its working cycle to opti-
refers to the management of electricity consumption ac- mize energy consumption); an early recognition of a power
cording to the concept of the smart grid, is that the time re- failure to avoid losing data related to the working status of
quired by the new generations of smart appliances to re- the appliance, a very useful function that helps designers of
place all the products currently present in the houses is digital control systems for household appliances to safely
about ten or more years, so it is too long to properly support manage power failures.
the parallel development of the new electricity networks.
This leads us to seek new solutions to accelerate the de- 3.6. Dynamic Demand Control (DDC).
ployment of appliances which are able to collaborate with Recent trials based on an old concept proposed in 1979
electric utilities and to support new value added services. by Prof. Fred. C. Schweppe of MIT (Boston, USA) are
showing how it is possible to contribute to the stability of
3.4. Power Modulation (PM)2, the communication tech- the electric grid through the synergistic and synchronized
nology developed by Indesit to solve the previous prob- action of digital appliances capable of continuously moni-
lems. toring the value of the mains frequency [21]. This is the
The above mentioned problems have suggested, since the concept of "Dynamic Demand Control" (DDC) [22-24], i.e.
early 2000s, the exploration of other paths in addition to the the possibility that a set of domestic appliances distributed
classical solution represented by a "communication node" over a large geographical area (maybe an entire country like
inside the household appliance, and Indesit Company de- the UK or Italy) and synchronized through the same fre-
veloped and successfully tested a technical solution that is quency, can act in a synchronous manner to transfer or ab-
very cheap and absolutely adequate for managing the ener- sorb power when the mains frequency, respectively, tends to
gy issues coming from the smart grid's opportunities [14], fall below a certain threshold lower than 50 Hz or to rise
and much more. above a certain threshold greater than 50 Hz (Figure 6).
This solution is called “Power Modulation” (PM) and, In this way the joint and synchronous action of thousands
thanks to the strong support of the University of Parma, it of appliances produces, through the sum of the small con-
has been implemented on silicon [15,16,17,18,19] by tributions of electrical power from each one, corrective ac-
Renesas Electronics Corporation (the Japanese Company tions which make it possible to ensure a substantially stable
balance between the power generated by the power plants
2 3
PM Technology is property of Indesit Company Spa For more info about Renesas RX210 microcontrollers family, please contact
(www.indesitcompany.com). Its technical support for producers of smart plugs Mr. Massimiliano Mazzoni (massimiliano.mazzoni@renesas.com).
4
The PMI peripheral, owned by Indesit, is freely available for manufacturers of
and household appliances has been totally delegated by Indesit to SPES
microcontrollers that want to use it inside their products. For more info, please
(www.spesonline.com). contact Valerio Aisa (valerio.aisa@consultants.indesit.com).

6. and that absorbed by the downstream users, minimizing pliances.
or even eliminating the costly interventions upstream
(switching on of generators for meeting the increased de- 3.8. The new generation of washing Machines produced
mand for power, or putting them in standby mode when by Indesit Company will be based on "power modula-
there is an excess of production) which cause great ineffi- tion" technology.
ciency and increased harmful emissions to the environment. Indesit is promoting PM by applying this technology on
Appliances which are best suited to performing this func- the new generation of its products. In particular, Indesit top
tion are refrigerators, water heaters, and HVAC systems, i.e. management has officially planned to use Renesas (PMI
those products that have a thermal accumulation (hot or based) RX210 microcontrollers for the next platform of
cold) which allows them to manage the DDC function, pre- washing machines, presently under development, which
serving the quality of their performance in any working will be on the market from 2014 (about four million pieces
condition. per year).
4. Introduction to Power Modulation
(PM) technology
PM Technology has the aim of adding point-to-point5
communication capability to a household appliance without
affecting its industrial cost, because it uses the same elec-
tronic resources already present in it.
To do this, the appliance should have a control system
based on a microcontroller and at least one electric load
controlled through a triac (T1, Figure 7).
The basic concept of PM is transmitting data by modu-
lating the power absorbed by one of its low power electric
loads. In this way, it is possible to transmit 50 or 60 bit per
second, depending on the mains frequency, i.e. 6 or 7 bytes
of coded data per second [15,16].
At first sight, this kind of transmission with such a lim-
ited baud rate seems to be too limited, but actually covers
perfectly what is necessary to satisfy all the needs related to
Figure 6. Dynamic Demand Control based on mains frequency. energy and healthcare issues and much more. In fact, to
transmit the status of the appliance, or some other infor-
mation like a time interval, a temperature, statistical data,
The DDC function is considered very important in some
diagnostic data, fault codes, and so on, only few bytes are
countries like Europe and USA, where trials are under way:
necessary.
the presence inside the PMI peripheral of a precise grid
Furthermore, PM communication is bidirectional: the ap-
frequency meter, which is capable of signaling via "inter-
pliance can receive 25 or 30 bytes per second, depending on
rupt" situations where this frequency falls below a certain
the mains frequency. This means the appliance can receive,
threshold or rises above another threshold, represents a
for instance, commands and information through a local
great opportunity to develop "DDC enabled" appliances,
network from an energy manager placed in the home; and,
which can help to restore the balance between the power
in turn, it can send, day by day, statistical and diagnostic
available on the grid and the power absorbed by the various
data to a remote service centre which offers the customer
electric users connected to it.
high level services like remote assistance and preventive
This feature can be effectively used in refrigerators, wa-
maintenance. For more details about PM technology, please
ter heaters and HVAC devices, that are capable of tolerating
see the referenced documents [16-20].
brief reductions of their power consumption. Indesit is
presently supplying Fridges for a DDC trial in the UK, 4.1. The new role of smart plugs (smart adapters).
supported by RLtech, NPower and the UK Government.
In order to connect a "PM enabled" household appliance
3.7. Liberalization of Power Modulation through a new to a local network, a special adapter (commonly called
generation of low-cost 32 bit microcontrollers dedicated “smart adapter”) placed between the appliance power cable
to smart appliances. and an electric socket is needed.
The “smart adapter” is simply a “smart plug” with a
The liberalization of PM (on March 29th, 2010) allows
power meter, a proper logic for decoding the data sent by
any manufacturer of household appliances to use it without
paying any royalty: therefore it is expected that this oppor-
5
tunity will speed up the diffusion of smart appliances. PM Technology is a point-to-point communication that allows a household
Indesit decided to share its patented technology with its appliance to directly communicate with a proper “smart plug” or “smart socket”
competitors in order to open the market of connected ap- that provides its power supply (from the mains) and the connection to a local
network.

7. the appliance, and means for its connection to a local net- easily implemented inside a traditional “smart plug” just by
work (any LAN technology can be used). It can also be in- adding the proper logic (software) to decode the data sent
tegrated inside a socket, so creating a “smart socket”. from the household appliance through the PMI peripheral
Thanks to Renesas Electronics Corporation and the Uni- device of Renesas RX210 microcontrollers.
versity of Parma [15-20], PM technology was embedded In practice, to add PM technology to a traditional
inside a microcontroller peripheral device (named PMI, "smart plug", it is necessary to perform the following
Power Modulation Interface) in order to guarantee repeata- two operations: insert proper logic to decode the data
bility of the data transmission from the household appliance. sent from the appliance and add proper hardware to send
For this reason, Indesit is today able to offer the license of data to it.
PM technology to any interested manufacturer of “smart Depending on the type of modification, we can have
plugs” and “smart sockets” to develop a new generation of two different solutions: the simpler one that is based on
devices that can interact with the grid and, at the same time, the unidirectional use of PM, and the second one based
are able to communicate directly with the household appli- on the bidirectional use of the same communication
ances that receive AC power supply through them. technology. In the first case, the appliance communicates
Smart plugs of the latest generation (Figure 8) are actu- to the smart plug its working status, the events of inter-
ally able to measure the energy consumption of the related action with the user (for healthcare applications) and
appliances and to share such data with proper energy man- other information useful for assisting the product re-
agement systems. They can also switch off the appliances motely; in the second case, the appliance can send data
through a relay, when necessary. and receive commands, working as a smart appliance
However, using smart plugs with on/off control is con- suitable for communicating with smart grids and for of-
sidered unacceptable, for several reasons (mainly for safety fering web based services.
issues) [25], by white goods manufacturers and consumers,
because such plugs typically don't know the working status 4.3. How a smart plug can monitor the status of the
of the related appliances and can cause malfunctioning or controlled appliance.
inefficiencies. Digital appliances (based on PMI microcontrollers) can
A good way to overcome this limitation is to inform the periodically send information about their operating status
smart plug about the working status of its appliance to al- (and many other data ...) by modulating the power absorp-
low them to interrupt the power supply only when this ac- tion of one of their triac controlled electric loads. Smart
tion doesn't cause problems: this communication can be plugs can capture the information about the working status
made directly by the appliance itself thanks to PM technol- of the related appliance by properly decoding the fluctua-
ogy. tion of the power absorbed by it, and then decide to open
the relay contact (switch off) only if the appliance agrees.
4.2. PM can promote a new generation of smart plugs. To do this, the smart plug needs a power meter and proper
Smart plugs of the latest generation (Figure 8), that are software to decode the digital data sent by the appliance.
able to communicate energy data to a local network, are al-
so suitable for adding PM communication, because it can be
Figure 7. PM communication system: (a) smart adapter, (b) digital household appliance.
4.4. Benefits for the appliance makers
White goods makers can sell PM enabled products with duces greater margins than a standard one, if its potentiali-
greater margins than standard ones, because these products ties are well presented; furthermore, it opens the white
have new potentialities based on a free connectivity that goods market to new business opportunities coming from
justify a major price. Of course, a PM enabled product pro- the offer of value added services based on the web.

8. Other benefits are: difficulties/cost of inserting and testing the node during the
 PM adds two-way connectivity at no cost to a standard production of the appliance, and the need for frequent and
appliance (provided with a digital control), useful for con- expensive updates of the communication protocol. While an
necting it to a local network for various purposes: energy appliance with a communication node inside can be used
management, remote assistance, monitoring and control of only with a home system that uses the same communication
the appliance, monitoring of the user's daily behavior, and technology, a PM enabled appliance can be connected to
so on. As an alternative to this approach, it should be nec- any local network, just using the "smart adapter" compati-
essary to put a "communication node" inside the appliance ble with the desired local network.
with a considerable cost (depending on the type of the  PM dramatically simplifies the tools necessary for
adopted communication technology), causing an increment testing an appliance during its production and also reduces
of the global cost of the appliance. Therefore, an appliance the testing time, because it is possible to send commands
with a communication node inside cannot be sold through directly to the appliance through its power cable to switch
normal distribution channels, but needs dedicated ones. ON and OFF each internal electric load, measure its ab-
 PM avoids tying an appliance to a specific communi- sorbed power (through the "smart adapter") and compare
cation technology through a "communication node" (stand- the measured data with reference values. Therefore the
ard or not) located inside the appliance itself, because it testing tools become simple and cheap, the testing time is
moves the node from the appliance to an external device reduced and consequently the cost of the testing process
(smart plug / smart socket): this makes it possible to elimi- decreases.
nate the cost of the node from the appliance, avoiding the
Figure 8. Smart Plugs, the retrofitting devices for traditional household appliances?
 PM allows a standard appliance to work as a peripher- with a communication node on board (that can be connected
al device of any home automation system (via a smart only to a local area network compatible with the technology
plug/socket) without adding cost to the product. Producers of that node), a "PM enabled appliances" can be connected
of home automation systems consider interacting with PM to virtually any local network, simply by using the smart
enabled appliances through proper smart sockets to be very adapter compatible with that network.
important, because it is a very simple and cheap way to  PM is suitable for AAL (Ambient Assisted Living) ap-
include standard household appliances in their system. plications where a PM enabled appliance, working as a "vi-
 PM is adaptable to any standard application profile tality sensor" of an elderly user who lives alone, can be as-
(e.g.: smart energy SEP1.X, future SEP2.0, Zigbee home sociated with any system of telecare/telemedicine. There-
automation profile improved with Energy@home results) fore a PM enabled appliance can also work as a "vitality"
and to any protocol (Zigbee, Z-Wave, WiFi, Bluetooth, sensor for the elderly.
Konnex, LonTalk, HomePlug AV, ...). Unlike an appliance

9. 4.5. Benefits for the final consumers  Very easy to implement: thanks to microcontrollers
The main benefits come from this fact: the consumer with PMI peripheral on board, like the Renesas RX210
buys a household appliance open to the future and he pays family, dedicated to “energy-aware” household appliances.
for a standard product. The expression "open to the future"  Capability to speed up the diffusion of smart appli-
means the possibility to connect the product to any future ances. The availability of a new generation of "smart plugs",
home network related to systems offering new services, that which thanks to PM technology are capable of communi-
the consumer will decide to buy when he wants. In other cating with their electric appliances, makes it possible to
words, an inexpensive PM enabled appliance has commu- speed up the diffusion of smart appliances interacting with
nication potentialities that can be used when the consumer the grid.
wants, over time. To connect the appliance to a home net-  Compatible with a standard “communication node”6 ,
work, the consumer will use a proper smart adapter, select- because the control system of the appliance can easily
ed according to the type of local network adopted for a spe- manage the two different communication channels.
cific application.  Suitable for supporting a new generation of “smart
Possible applications are: plugs & smart sockets”, connectable to any local network
 Energy management (requires the presence of an en- and able to communicate directly with the related household
ergy management system). appliance.
 Energy monitoring (monitoring of the energy con-  Suitable for remotely assisting household appliances
sumption of the appliance). without adding any cost to the product. It is possible because
 Home automation (the system can monitor the work- the new generation of household appliances based on
ing status of the appliance). Renesas 32 bit microcontrollers (RX210 family) can execute
 Remote control through the internet (the consumer can complex routines for auto-diagnosis and will be potentially
remotely control the appliance, when applicable). able to capture early symptoms of possible faults – with the
 Ambient Assisted Living applications (applications for help of proper sensors - to enable preventive maintenance
helping the elderly in daily life). services.
 Application for smart phones or smart tablets that al-  Simpler and shorter in-line test of the appliance, with-
low the consumer to interact with his PM enabled applianc- out the need to use expensive and complex tools. In fact,
es. thanks to the “power metering” function of the “smart
 Applications that improve consumer awareness on en- adapter”, it is possible to send to the appliance, for instance,
ergy consumption, thanks to the nature of PM which means commands for sequentially activating and deactivating each
the presence of a power meter. electric load of the appliance, at the same time measuring its
electrical quantities like the absorbed current and the cosphi
4.6. Main features of Power modulation (PM) (displacement between the mains voltage and the mains
current related to the electric load).
Summarizing, the main features of PM technology are the
following:  4.7. Indesit strategy on connectivity.
 No cost for the manufacturer of household appliances,
because the communication is managed by the same control As already mentioned, Indesit is partner of the important
systems of the appliances, based on PMI microcontrollers, project named Energy@home [7], along with Enel, Electro-
like the Renesas ones (new 32-bit RX210 family). Further- lux and Telecom Italia, and intends to base its strategy for
more, after the signature of a free license agreement between connectivity on Zigbee technology and its approach is two-
Indesit and Renesas (March 29-th, 2010), no royalty is due to fold:
Indesit for using PM enabled microcontrollers supplied by  Using Zigbee technology in high-end products, fol-
Renesas. lowing the general trend worldwide based on appli-
 No need to tie the appliance to a specific network pro- ances with a communication node on board.
tocol, because the connection to a local network is managed  Adopting PM for the entire production of digital ap-
by the “smart adapter”. In other words, the communication pliances (including high-end products): in this case
node (necessary) is moved from the appliance to the smart the Zigbee based communication node is placed in-
adapter, and all the networking issues are managed by this side the smart plug (smart adapter).
adapter. Therefore, PM technology is compatible with vir-
tually any network protocol.
 Fully suitable for interacting with a smart grid, because
5. Conclusions
PM technology is able to manage all the necessary infor- Power Modulation (PM) - a simple and very cheap
mation. communication technology developed by Indesit over the
 Enabler of the role of "vitality sensor" for a household
appliance.
 Capability to perform the energy function called Dy- 6
A white goods manufacturer can use PM technology as the basic communica-
namic Demand Control easily [21-24], because the same tion system for the entire production of digital household appliances, because it
PMI peripheral of Renesas RX210 microcontrollers provides doesn’t cost. When a higher rate communication is requested (case of high end
a precise measurement of the mains frequency and compares products, for instance), a standard communication node can be added without any
it with a programmable threshold. problem.

10. last decade to overcome the obstacles encountered in at- ident Marketing, Sales and Innovation at Indesit Company
tempting to produce “smart appliances” for the connected Spa during the development of the Ariston Digital system,
home - has good potential to become a "de facto" standard and later European Commercial Director Integrated Home
able to transform traditional household appliances into Solutions at Whirlpool Corporation) for the patient revision
smart ones without increasing their industrial cost. of this article, for his valuable advice and for what done in
PM allows an electric appliance to exchange data with the past to support the development of the above mentioned
local networks through a new concept of smart plug, capa- networking solutions.
ble of working as a network-adapter to avoid a direct
connection (risky and expensive) of the appliance to a do-
mestic LAN.
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