Cable length
The length of the cable used to connect the surge protector to the network.
The longer the cable, the farther from the outlet you can install the device. On the other hand, a long cable can be inconvenient over short distances. Models on a coil are deprived of this drawback (see "Type"), this moment is compensated by the actual presence of the coil, but they differ in large dimensions and heavy weight. So when choosing, it is far from always worth chasing the maximum length of the wire.
Max. power
The highest power consumption of the connected devices that the surge protector can tolerate without consequences (to be more precise, with which it can work indefinitely without overloads, overheating, etc.).
This limitation is due to the fact that the higher the power at the same voltage, the higher the current passing through the equipment (in this case, through the surge protector); and off-design currents can lead to breakdowns and even accidents. And although in order to avoid these consequences, modern filters often provide various types of protection (see above), however, the operation of protection is still an emergency situation that is best avoided. Therefore, it is worth choosing a model according to this parameter in such a way that the maximum filter power is at least not lower than the total power consumption of the load. And it is best to have a margin of 20 – 30% — this will give additional guarantees in case of various deviations in the operation of the connected equipment.
Separately, it is worth highlighting the situations when the filter is planned to be used for the so-called reactive load — electrical appliances that widely use circuits on capacitors and/or inductors, for example, power tools or refrigeration units. The total power consumption of such devices (written in volt-amperes) can be much higher than the active power (which is indicated in watts). The recommended line filter power in such cases is calculated using special...formulas that can be found in the relevant sources.
Max. energy absorption
The maximum energy absorption provided by the mains filter, namely, the maximum pulse energy at which the device can safely absorb and dissipate it, completely protecting the connected load. The higher this indicator, the more reliable the filter, the more powerful power surges it can handle. In inexpensive models, the maximum absorption is calculated in tens of joules, in the most advanced models it can exceed 1000 J and even 2000 J.
Operation indicator
The presence in the design of the surge protector of a special indicator (usually in the form of a light bulb) that indicates that the device is turned on.
This function provides the presence of at least one common indicator; and on models with switches per outlet (see below), additional indicators can be installed on the outlets. Anyway, such equipment makes working with the surge protector more visual, allowing you to immediately assess the status of the device and avoid some unpleasant situations (for example, imaginary equipment breakdowns — when a “faulty” device does not work just because the filter is not turned on).
The indicator can be installed directly in the switch (general or for each outlet, see the relevant paragraphs for details).
Power switch
—
Switch on the body. This function allows you to turn off the power to the load without disconnecting the filter itself from the mains — in other words, it eliminates the need to once again remove the filter plug from the outlet and insert it back. Most often, the switch controls all filter outlets, however, there are models where some of the connectors are bypassed and are always energized, regardless of the position of the switch.
—
A switch for each outlet. This feature makes it easier to manage the power of connected devices: unplugging and plugging individual outlets is usually easier and faster than unplugging and plugging back in. Thus, electrical appliances used with such a filter can be kept constantly connected to it, turning off and on individual outlets as needed.
— Switch for each circuit. The function is used in models with numerous outlets. Allows you to simultaneously disable half of them, leaving the rest working. It combines the convenience of the points listed above and at the same time does not clutter up the device with unnecessary switches.
It is also worth noting that there are models that combine both a switch on the case and a switch for each outlet.
Grounded sockets (type F)
The number of
sockets with type F grounding, provided in the design of the mains filter.
In this case, we are talking about full-size European type F sockets with metal ground clamps on both sides at the edges of the socket. The "socket" in this case means a CEE 7/4 ("Schuko") standard plug. Grounding is required for the safe operation of some types of electrical appliances, in particular, washing machines and other machines that work with water, refrigerators, computers, audio equipment, etc. A detailed list can be found in the reference literature. If you plan to connect such devices through the filter, this filter must have sockets with grounding.
Max. charging current
The current output by a USB connector when a charging gadget is connected to it.
The higher the current, the faster the battery can charge. However, when choosing, note that in order to use a high current strength, the connected device must also support it. Basically there are
USB with a current strength of 2.1 A,
2.4 A and
3 A.
It is also worth noting that when using several USB ports at the same time, the current strength is significantly reduced.
Power (with 1 device)
The maximum power that a USB port can produce when connecting only one gadget.
Higher power output speeds up the charging process. At the same time, there are a number of nuances associated with this parameter. Firstly, the appropriate power must be supported not only by the port, but also by the gadget being charged - otherwise the speed of the process will be limited by the characteristics of the gadget. Secondly, to take full advantage of the capabilities, you may need to support not only the appropriate charging power, but also a specific fast charging technology. Thirdly, in filters with several charging connectors, the maximum power per device can only be achieved if the other ports are not used.
Charge current
Current value for all USB ports of the device. Allows you to understand how much maximum you can squeeze out of the device, i.e. how much current will be supplied to each port at maximum load. As for the maximum value of the current strength, it cannot be determined by this indicator.
