Comparison Xiaomi Smart Plug 2 Wi-Fi vs Ajax Socket

— Leading (Master). Sockets that can work completely independently and do not require connection to external gateways — unlike the Slave models described below. At the same time, some of the Master devices themselves are able to play the role of a gateway for connecting slave sockets. Anyway, if you need only one smart socket, or if you are building a system of such sockets from scratch, you should pay attention to the leading type models.

— Slave. Sockets that are not able to work independently and are connected through additional equipment. In other words, such a socket accepts commands from the user and transmits information to him not directly, but through control equipment — for example, a Master socket (see above) or a special gateway for a smart home system. It makes sense to pay attention to slave models if you already have a control device or you plan to build a system with several smart sockets — the “1 Master and several Slave” scheme will cost much less and will be easier to set up than several separate Master- sockets. When buying a slave socket, you need to pay special attention to compatibility — different technologies can be used to communicate with master devices, which are not always compatible with each other.

Control method supported by the device.

Nowadays, smart sockets are mainly used by smartphone control, from the remote control or from the control unit. Here are the main features of each of these options:

— From a smartphone. Control via a smartphone or other similar gadget (for example, a tablet) — most often with the help of a special application, but there are exceptions. The method of communication in this case can be different: there is both a direct connection via Wi-Fi or Bluetooth, and the possibility of transmitting remote commands via a GSM mobile network or via the same Wi-Fi; each option has its advantages and disadvantages, for details see "Communication protocols". However, anyway, smartphone control itself has a number of advantages. So, it allows you to use a gadget already available on the farm without purchasing special remotes or other equipment. At the same time, the mentioned communication protocols are supported by all modern smartphones, in tablets, difficulties can arise only with GSM, and GSM sockets themselves often allow control even from ordinary mobile phones (not smartphones). Installation and configuration of models with this type of control is usually quite simple and does not require much effort. And control applications are usually available for all major mobile operating systems (Android, iOS); their functionality...can be very extensive, and the interface is most often convenient and intuitive. The main disadvantage of this option can be called some complexity (and sometimes impossibility) of integration into more extensive systems, such as a "smart home". On the other hand, this moment is relevant only for individual communication protocols, and even there it is not so often critical; so it is control from a smartphone that is most popular nowadays.

— Remote control. Controlled by your own remote control supplied with the socket. The remote control usually works wirelessly, and the specific communication technology may be different: some models operate in the infrared range and require line of sight, others use a radio channel and “reach out” even through a wall. Anyway, this option is convenient because everything you need for control is immediately included in the package, the user does not need to use a separate gadget (unlike the models described above, designed for a smartphone). Yes, and the connection is very simple, without the need for extra settings. On the other hand, the remote is usually less functional than the mobile app; it operates only within the same premises (apartment, office, etc.), and there is no talk of remote control; and controlled sockets are strictly independent devices that are not able to interact with other components of security systems or "smart home". Therefore, this option nowadays is quite rare.

— Control block. Management through a separate control unit (gateway). The role of such a unit can be played by a central device for alarms or smart home systems, a specialized gateway for smart sockets, or even a compatible Master socket (although models with this type of control may also be classified as Master; see "Format of operation"). Anyway, in this case, the commands from the user do not come directly to the outlet, but first to the gateway and from there to the device.
The main convenience of this option is that the control unit can be chosen at your discretion — depending on specific needs and other features of the situation. Also note that the connection of such sockets with the gateway is most often carried out using one of the special protocols — Z-Wave, ZigBee or Jeweler (for more details, see "Communication Protocol"). This, among other things, allows the sockets to be integrated into existing security or smart home systems if they use the same protocol. Of the noticeable disadvantages of this type of control, one can first of all note the need for a control unit. In addition, connecting and configuring such outlets is somewhat more complicated than the varieties described above (although manufacturers are trying in every possible way to simplify this task for ordinary users).

— From a computer. In particular, such control is relevant not so much for smart sockets as for smart extension filters. They are able to connect to the network via LAN or USB B, which allows you to receive command signals.

The communication protocol (standard) used by the receptacle to communicate with the control device.

Nowadays, among smart sockets, only wireless standards are used, which can be divided into two types. The first is the commonly used Bluetooth, Wi-Fi and GSM technologies used to connect to a smartphone (see “Management”); the second is specialized communication formats Z-Wave, Zigbee and Jeweler, intended for protection / smart home systems and used when controlled through a control unit (see ibid.). Here is a more detailed description of each of these standards:

- Wi-Fi. The most popular communication protocol among sockets controlled from a smartphone. Initially, this technology was used mainly for wireless access to local networks and the Internet, but nowadays it is also possible to directly connect various devices via Wi-Fi. Accordingly, the specific method of implementing such a communication may be different: some models connect to a router and are accessible via LAN or even remotely via the Internet; others connect to a smartphone/tablet and can only be controlled at a direct communication distance; still others allow both formats of work. It is worth clarifying these details separately; however, in any case, it is precisely this versatil...ity that is not least responsible for the widespread use of Wi-Fi sockets. The second advantage of this protocol is its good communication range: it is on the order of several tens or even hundreds of meters (which, among other things, allows you to work reliably through walls). It is also worth noting that Wi-Fi modules, by definition, are found in all modern smartphones and tablets; and some sockets allow control from other devices - for example, laptops and even desktop computers (including via networks).
Among the general disadvantages of this technology, one can note only its higher cost and lower energy efficiency than Bluetooth. However, the first point is most often outweighed by the advantages, and the second is relevant mainly for control gadgets, since the sockets themselves are constantly receiving power from the network and have almost unlimited autonomy. In addition, it is worth keeping in mind that some Wi-Fi sockets only work through a wireless router and do not support a direct communication; however, given the prevalence of Wi-Fi networks in our time, this point also cannot be called critical.

— Bluetooth. Another technology used to connect sockets with smartphones and tablets. It is noticeably less common than the Wi-Fi described above, since it is noticeably inferior in capabilities to this standard. Firstly, Bluetooth communication is carried out only directly between devices, so there is no question of remote control. Secondly, the actual range of such communication usually does not exceed 15 - 20 m, and with large wall thicknesses it can be significantly less. As for the advantages of Bluetooth, they include, first of all, low cost and the ability to work without routers and other intermediate equipment (while many Wi-Fi models only work if there is a wireless network). In addition, such a communication is characterized by low power consumption, but in the case of smart sockets this point cannot be called particularly significant. The fact is that the sockets themselves are constantly connected to the network and they do not need to save much energy; and the control gadget should be located in close proximity to sockets, and there are usually no problems charging its battery.

- GSM. Connection via mobile network; the term “GSM” in this case is quite arbitrary, since such sockets can also work in more modern 3G and 4G LTE networks. To use this communication, you need to purchase a starter package from a mobile operator and install a SIM card in a smart socket. As a rule, control via GSM is carried out using calls and/or SMS to the telephone number assigned to the outlet; Often, it is also possible to send response notifications (text or even voice), and to protect against unauthorized access, a list of allowed numbers is stored in the device’s memory. The key advantage of this communication method is the ability to access the outlet settings from anywhere in the world where there is mobile treatment. In addition, you can make calls and send SMS from any mobile phone, it does not have to be a smartphone. On the other hand, control via a mobile network provides significantly less capabilities than other protocols, and the communication itself requires financial costs. So it hardly makes sense to pay attention to such sockets if most of the time they have to be controlled “locally”, from the same home or office where these devices are installed.

- Z-Wave. A wireless communication standard specifically created for automation and control systems, including alarms and smart home. Along with what is described below, Zigbee is one of the generally accepted protocols used in such systems; and in smart sockets controlled through a control unit, it is also most popular. This is due to the fact that such a communication is simple and inexpensive to implement, while being quite functional and practical. It provides for the transmission of the simplest and shortest control commands, which helps save energy, and operates in the range up to 1 GHz, making it not susceptible to interference from Wi-Fi and Bluetooth devices. In addition, in networks based on Z-Wave, it is possible to use a MESH type topology - when each individual device is also a full-fledged repeater of signals from other system components. Devices in networks of this type can choose any route for the signal, through any number of intermediate nodes, depending on the situation. For example, if direct communication between two nodes for some reason turns out to be impossible, the data will be sent “bypass”, through other network devices, and the system will automatically determine the most optimal route. This makes it easy to organize large networks with a large number of devices and a large treatment area.

- Zigbee. Another communication protocol created for automation systems (including smart home), alarms, industrial control, etc. In many ways it is similar to the Z-Wave described above: it allows you to transmit control signals with low energy costs, as well as create networks MESH with signal routing through several nodes and automatic selection of the optimal route taking into account the current situation in the network. The main differences between Zigbee and Z-Wave are the high protection of communication channels from hacking, as well as the ability to provide high response speed. The downside of these advantages is the higher cost of implementing this protocol, while speed and protection usually do not play a key role in smart plugs. Therefore, slightly fewer devices are produced for this communication standard than for Z-Wave.

— Jeweler. A proprietary communication protocol developed by Ajax Systems. The company's specialty is signaling, and this protocol was originally created specifically for such systems - this is the reason for its advanced characteristics. In particular, Jeweler provides a communication range of up to 2 km at very low energy costs, has high-quality hacking protection, allows you to change frequencies when trying to jam the operating range, and supports simultaneous communication of up to 150 devices per gateway. On the other hand, for smart plugs most of these features are unnecessary, although they significantly affect the cost. However, the main disadvantage of this protocol is that its use is limited to devices from a single manufacturer. So it makes sense to purchase sockets with Jeweler support if your home uses (or plans to use) an alarm system from Ajax Systems.

Nowadays, you can find different smart home platforms, the most popular are Apple HomeKit and Google Home (see below). However, there are other options for proprietary systems - as a rule, they are sold by manufacturers for their smart home devices.

- Apple HomeKit. Smart home technology developed by Apple and designed to be controlled from Apple devices (iPhone smartphones and iPad tablets, PCs and laptops on macOS, wrist gadgets on watchOS and smart video equipment on tvOS, as well as HomePod smart speakers). One of the most striking features of this technology is the ability to control components (including smart sockets) through the Siri voice assistant. Specific HomeKit functionality is constantly being expanded and improved; however, if you are a fan of Apple technology, when choosing smart sockets you should definitely pay attention to models that support this technology.

- Google Home. Similar technology from Google. Compatible components (including smart plugs) can be controlled from any device with the Google Home app installed; Today such an application is available for both Android and iOS. In addition, there are specialized control devices - most notably the Google Nest line of smart speakers (which was originally called Google Home), equipped with a built-in Google Assistant.

The type of voice assistant supported by the device.

By itself, the support of a voice assistant makes it possible to control a smart socket / extension cord using voice commands. However, note that this is not about an assistant built into the socket itself, but about guaranteed compatibility with the gadget where the corresponding assistant is installed. Thus, to use this feature, you will need an additional device with a built-in voice assistant — a smartphone, tablet, smart speaker (Amazon Echo, Apple HomePod, Google Nest), etc.

The most popular voice assistants nowadays are Amazon Alexa, Apple Siri, Google Assistant. A smart socket can be compatible with one of them, or with several at once; the specific functionality available from the voice assistant should be specified separately in each case. In addition, you should pay attention to the supported languages.

Note that the support of assistants is directly provided for in some smart home systems. For example, the Apple HomeKit specification initially includes the use of Siri, and Google Assistant is available in Google Home if an Android gadget is used for control (more on HomeKit and Google Home, see above).

Various functions and possibilities of a smart plug. These may be features related directly to power supply ( timer, scheduling, energy consumption statistics); features that facilitate connection and integration into "smart home" systems (connection of additional sockets, IFTTT programming); various sensors ( temperature sensor, including a thermostat, humidity sensor, motion sensor); safety features ( "baby" curtains, water protection, protection against power surges); and even specific equipment like a night light. Here is a more detailed description of the main options that are relevant for smart sockets nowadays:

— Timer. A function that allows you to turn off the power after a user-defined period of time. The timer is useful primarily in cases where the electricity needs to be turned off at a certain moment, but the user cannot do this manually — for example, if it is time to go to work and it will not work to wait for the turn off time. In addition, this function makes it easier to keep track of the operating time: instead of controlling the time by the clock, the user simply nee...ds to set the timer on the outlet.

— Scheduled work. Possibility to set the schedule of switching on and off of electricity. This is a more advanced feature than the timer described above: the timer must be restarted each time it fires, while the schedule only needs to be set once. In addition, the schedule allows you to manage not only shutdowns, but also inclusions. This feature provides many options for setting up the "smart home". For example, if you have a nightly electricity tariff, you can configure the outlet so that powerful appliances like boilers turn on only during the “grace” period. Also, you can “tie up” an automatic irrigation system, yard lighting, etc. to a smart socket with a schedule. Note that the specific capabilities of the programmer may be different; the simplest option is the ability to set a programme for a day, however, there are models with a schedule for the days of the week.

— Power consumption statistics. The ability to keep energy consumption statistics with the help of an outlet, in other words, to calculate electricity costs for a certain period. At the same time, the simplest models are only able to display the total flow, more advanced ones can determine at what time the flow was maximum / minimum and even build graphs. The information collected by the socket is transmitted to a smartphone or other gadget via Wi-Fi / Bluetooth or to the control unit of the smart home system (see "Control"); models with control via remote or telephone (GSM) do not have this function.

— Temperature sensor. A sensor that monitors the temperature of the air in the room. How to use this feature may vary depending on the model. So, some sockets with a similar sensor also have a thermostat for automatically maintaining the microclimate. In other devices, the temperature sensor is used only to transmit data to the user, and the person, if necessary, takes some action. There is also a simple fire alarm function — when the temperature rises above a critical level, the socket sends an emergency notification to the user (or control unit).

— Thermostat. An additional feature found on models with a temperature sensor (see above). Allows you to use a smart socket to automatically maintain a certain temperature in the room. To do this, you need to connect a heater or other similar device through such an outlet and set the desired temperature in the thermostat settings: when the air cools down, the thermostat will turn on the power to the heater, and when the set temperature is reached, turn off the heating.
We emphasize that thermostats in modern smart sockets are most often designed specifically for heating; the cooling mode in such regulators is almost never found. This is due to the fact that air conditioners used to lower the temperature, for the most part, have their own thermostats and are not designed to be controlled by turning on and off the external power supply.

— Humidity sensor. A sensor that monitors indoor air humidity. The ways of using such a sensor can be different: in some models, it only transmits data on humidity to the user, in more advanced sockets, automatic switching on or off when a certain level of humidity is reached. Anyway, it makes sense to pay attention to models with such a sensor if it is planned to connect humidity control equipment (humidifiers or dehumidifiers) through them. Such a need may arise, in particular, in a nursery for a newborn: dry air is undesirable for a baby, so humidifiers are often used in such rooms.

— Motion Sensor. A sensor that reacts to movement in the room. The specifics of the use of such a sensor in different models may be different. For example, some models can play the role of a security sensor or an automatic light switch: they send a signal to the security system or turn on the lamp as soon as the sensor detects movement in the field of view. Another option for using this function is automatic protection in case of user forgetfulness: for example, if he plugs an iron into a smart socket and leaves the room, the sensor will turn off the power some time after it stops detecting movement.

— Protective curtains from children. Shutters that cover the holes in the outlet from foreign objects — for example, pens or screwdrivers that a curious child can try to put into the outlet. At the same time, the curtains are arranged in such a way that they do not interfere with inserting a conventional plug.

— Water protection. The outlet has a reinforced protection against moisture. It is these devices that you should pay attention to if you plan to use the smart socket on the street or in a room with high humidity (bathroom, indoor pool, etc.). At the same time, it must be borne in mind that the level of water protection in different models may be different, it must be clarified before use.

— Nightlight. The ability to use a smart socket as a night light — a dim lamp for night lighting. To do this, the body of the device provides its own light sources, usually based on LEDs. The classic way to use a night light is in the children's room, so that pitch darkness does not frighten the baby. However, this function can also be useful for adults — in case you have to get up in the middle of the night (or early in the morning, it has not yet dawned): it is easier to get to the main switch even in the dim light of a nightlight than in complete darkness.

— Protection against voltage surges. Protective system that protects the load connected to the outlet from voltage fluctuations in the network. Usually, relatively small and short-term power surges are extinguished by the outlet itself; if the protection capabilities are not enough, the power is automatically turned off, protecting the load from damage. Such protection is especially important for sensitive electrical appliances such as televisions or audio equipment; it will not be able to replace a full-fledged voltage regulator, however, for more or less stable networks in which fluctuations rarely occur, it is usually quite enough.

— Connection of additional sockets. Possibility to connect additional slave sockets to a smart socket of Master type (see "Type"). It is worth choosing a model with this function if you want to build a system of several smart sockets controlled through one of them. In particular, this is the most convenient way to build networks with remote control over the Internet (see "Management"): a set of one master and several slave sockets will be easier to connect and cheaper than several separate Master sockets.

— IFTTT support. Support socket technology IFTTT. This technology is used to combine different types of devices within the "smart home" and other similar systems and organize the work of these components according to the principle "if (...) — then (...)". For example, if there is an opening sensor on the door, you can configure the smart socket so that it turns on its own night light when this sensor is triggered — and the person who enters does not have to look for the switch in complete darkness. It is also possible to create longer, multi-stage chains of commands (for example, "sensor triggered — lighting turned on — ventilation started — switching on a smart socket with a thermostat"). It is worth noting that these features may be available without IFTTT; however, this technology provides a number of advantages. Firstly, it allows you to organize interaction between devices from different manufacturers without any difficulties. Secondly, IFTTT has tight integration with a number of popular web services like Gmail. Facebook, Instagram, etc., as well as special applications, thanks to which such systems can also respond to very specific events — for example, receiving an e-mail from a specific addressee.
As for smart sockets specifically, IFTTT support in them primarily simplifies integration with other components of a smart home or automation system.

The maximum load power that can be connected to the network through a smart socket. If you plan to power several devices through the device, accordingly, you need to take into account their total power.

Permissible power up to 2 kW is considered relatively low, but it is quite enough for most household appliances that do not have high power consumption. For example, such values will be enough for a household lamp, a medium-sized TV, a home air conditioner, a microwave oven, etc. Devices with a maximum power of 2 to 3 kW are suitable for more “gluttonous” equipment like an electric kettle or boiler. And the most “hardy” smart sockets are limited from 3 to 3.5 kW, they will be compatible with any electrical appliances that are generally designed to work from an outlet (recall, power of more than 3.5 kW requires connection directly to the shield, ordinary sockets are no longer designed for it).

The maximum load current for which the smart socket is designed. This parameter is directly related to the maximum power (see above) — we recall that the power is calculated by multiplying the current by the voltage. Thus, if the maximum power is, for example, 2200 W, then the maximum load will be 2200/220 = 10 A.

The permissible load of less than 10 A for modern smart sockets is considered low, 11 – 15 A is considered average, and the maximum indicator is actually 16 A — ordinary wall sockets do not initially assume a higher load. Equipment that consumes a current of more than 16 A requires a special connection with special control automation; smart sockets are not used for such devices.

The operating temperature of the device is the range of ambient air temperatures at which the socket / extension cord is guaranteed to remain operational.

All smart sockets and extension cords easily tolerate “room” conditions with a temperature comfortable for a person. Therefore, if the device is bought for an ordinary residential or office space, you can ignore this indicator. But if the outlet / extension cord is to be used in a more extreme environment (for example, in an unheated garage), you should make sure that the selected model can normally endure the corresponding temperatures. This is especially true with regard to resistance to cold: frost -resistant devices can be found on the market, but there are quite a few of them.