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. load
The maximum current that the surge protector can pass through itself for an unlimited time without the risk of overheating, breakdowns and other troubles.
This parameter is directly related to the maximum power of the filter (see above): power is the current multiplied by the voltage. Thus, for example, for a standard 230 V model with a maximum power of 2200 W, the maximum load will be 10 A. Note that the characteristics of modern filters may not correspond to such calculations — for example, the same 10 A can be claimed for a 2500 W model . However, this is not something extraordinary: the difference in figures may be due to active and reactive power (see "Maximum power"), the characteristics of single-phase filters (without 400 V sockets, see above) can be given both for 230 V, so for 230 V and even 240 V, figures may be rounded for readability, etc.
Anyway, the practical value of the maximum load is the same as the maximum power: it should not be less than the current supplied to the connected electrical appliances (otherwise the protection may trip, or even break). And they use this parameter, along with the maximum power, because in some cases it is easier to evaluate the characteristics of the load (and filter requirements) in terms of current consumption, and not in terms of power.
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.
Wire section
The cross-sectional area of the wire used to connect the filter to the network. The larger the cross-sectional area, the thicker the wire, the more reliable it is and the more current it can pass without overheating. Accordingly, thick wires (
1.5 mm² and
2.5 mm²) are a must for high power devices. At the same time, modern manufacturers, usually, choose the cross-sectional area in such a way as to guarantee the safe operation of the filter at the claimed maximum power (see above). Therefore, in fact, a model with a thicker cable than other similar devices should be chosen if it is supposed to be used in unstable networks in which power surges often occur. If the cross-sectional area seems too small for you (
0.75 mm² or
1 mm²) for the claimed power, there are special formulas that allow you to check the validity of such doubts.
Wall mount
Availability
of fastening on a wall in a network filter design. Such fastening most often has the form of a characteristic eyelet (loops), designed to be put on a nail driven into the wall or other similar detail. And the installation on the wall itself is convenient in that the filter can be quite close to the user, and besides, it does not take up space on the floor (which, among other things, minimizes the risk of stepping on the device, damaging it during cleaning, etc.) .
Outlets location
Options for placing sockets on the body of an extension cord or surge protector.
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Along the hull. Devices with the layout of sockets in one slender line, which is extended along the entire body of the extension cord or surge protector.
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In 2 rows. A popular scheme with the arrangement of sockets in 2 rows is on both sides of the upper plane of the device housing.
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In a circle. This category includes all extension cords and surge protectors with sockets in the form of a full circle or a semicircle.
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On both sides of the body. Sockets on several side faces of the case are found in compact cube models and in advanced surge protectors with relocated sockets on both sides of the case, which makes it easy to connect a large number of consumer devices.
Socket plugs
Placement of plugs in sockets of an extension cord or surge protector relative to the device case.
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at an angle. Seats with holes for plugs in such models are rotated at an angle of about 45 ° relative to the plane of the case. Such an option for placing plugs allows for convenient inclusion of plugs so that they do not interfere with each other and do not overlap adjacent slots.
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Parallel to the body (180°). The holes for the plugs in this layout are arranged in sockets parallel to the body of the extension cord or surge protector. Large plugs are included in them perpendicularly, i.e. at an angle of 90° from the side of the "tail" with a network cable in relation to the axis of the device body.
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Perpendicular to the body (90°). A fairly rare form factor that involves the placement of seats for a plug with a plug perpendicular to the axis of the device case. As a rule, openings at an angle of 90 ° relative to the housing are found in models for compact flat plugs and in surge protectors of atypical form factor. They can also coexist with sockets where the holes for the plugs are located at an angle.
- At an angle and parallel to the body. Combined variant of the layout of the holes for the plug, combining sockets with seating at an angle and parallel to the axis of the body of the extension cord or surge protector.
- At an
...angle and perpendicular to the body. A variety of network filters and extension cords with different arrangements of holes in the mounting sockets. Most of them are placed at an angle with respect to the axis of the body, and one or more - perpendicular.Protection level
The degree of protection of electrical appliances is regulated by the international standard IP (International / Ingress Protection Rating). For power strip outlets, the most commonly used protection standards are IP20 and IP44.
Only ordinary household models do not have protection. Devices in the IP20 category have basic protection against dust, but they are not protected against moisture. Sockets rated IP44 and above are capable of withstanding both dust and moisture. Models of this class can be safely used in bathrooms and other rooms with a high level of humidity.