International plug
Sockets that have a
universal socket suitable for different types of plugs. Most often, such sockets are made compatible with three types of plugs: Euro sockets, American "Type A" plugs that have two parallel flat contacts, and Type I plugs that are used in China and Australia and have three flat contacts at an angle. A smart socket of this format actually also plays the role of an adapter for plugs. Note that the own plug in such a smart socket may differ from the standard Euro plug, it is advisable to specify this point when buying separately.
Number of sockets
The number of power sockets provided in the design of the device, in other words, the number of own sockets on the case. This number corresponds to the number of consumers of electricity that can be simultaneously connected to the device without the use of splitters or other similar accessories.
Most
multi-jack models are smart extension cords (see "Type"), in such devices the number of connectors can be up to six. Smart sockets (both conventional and built-in — see "Type") have only one plug as standard; exceptions are extremely rare, and even in them the number of power sockets does not exceed 2. At the same time, individual sockets in such paired models often have independent control, that is, one smart socket replaces two separate models (however, this nuance needs to be specified separately).
Recall that when using a device with several sockets, you need to be especially careful to ensure that the total power of the connected devices does not exceed the permissible parameters for both the smart socket / extension cord itself and the household socket from which energy is supplied.
Communication protocol
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.Smart home system integration
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.
Voice 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).
Maximum power
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).
Maximum load
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.
Operating temperature
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.