Comparison APC PZ42I-GR vs REAL-EL RS-6 Extra 1.8m

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.

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.

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.

— 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.

The type of plug (plug) used to connect the surge protector directly to the network.

— Normal. A traditional plug for sockets, which is standardly used in Europe and the post-Soviet space. The official name is CEE 7/4, or Schuko. If the filter is planned to be connected directly to a regular household network, you should pay attention to this type of plug. Also note that in models with 400V outlets (see below), a normal plug refers to a standard 400V plug.

— UPS (for UPS). A plug designed to fit into a three-prong IEC 60320 C13 socket, also known as a "computer socket". Such connectors are often found in uninterruptible power supplies, but they are practically not used as ordinary power outlets. Therefore, buying a filter with such a plug makes sense only if it is planned to be used in combination with a UPS.

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.

— Short circuit protection. Short circuit (short circuit) protection system — situations when the impedance in the circuit drops sharply, for example, due to a metal object falling between the socket contacts. It reacts to a sharp increase in current and opens the circuit, allowing you to avoid damage and fire equipment.

— Voltage drops protection. Protection against power surges in the network. A filter with this function is able to completely cut off power that exceeds the allowable rate set by the manufacturer, protecting the load from damage. Note that the surge protector is not able to replace a full-fledged stabilizer or voltage relay; however, in more or less high-quality networks that are not subject to strong fluctuations, a filter is quite enough.

— Overload protection. In this case, overload means a situation when the load power exceeds the values \u200b\u200ballowed for a given network filter. This situation is similar to the short circuit described above — high currents go through the filter; however, overload has its own specifics, so protection against it can be provided as a separate system. However, the principle of operation of such systems is classic: when the permissible power is exceeded, it turns off the power, preventing breakdowns and fires.

— Varistor protection. A kind...of protection against short-term power surges in the network, built on varistors — variable impedance resistors. The impedance of such a resistor under normal conditions is in the millions of ohms, but it drops sharply if the input voltage increases above a certain value. Due to this, in normal mode, the protection practically does not affect the circuit, and with a high-voltage pulse, excess energy “merges” through the varistor and dissipates in the form of heat. The ability of varistors to absorb energy is not infinite, therefore, to protect against overheating, the design usually provides for a temperature sensor with an automatic switch.

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.) .