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August 12, 2017 18:07

6 important criteria for selecting a circuit breaker

The main purpose of the circuit breaker - protection of the wiring short-circuit current (hereinafter SC) and power overloads.If there is an emergency and home wiring will take place over-current, cable insulation instantly melted, and the wiring itself breaks out as sparklers.The result is, as you know, deplorable - the risk of fire and even worse - an electric shock.To this did not happen, in the flat panel it is necessary to set the machine (and preferably several) with suitable characteristics.About how to choose a circuit breaker on the current cross-section of the cable and the rest of the specifications, read on!Immediately advise necessarily view the video instructions provided below, which clearly shows the method of calculating the desired automation parameters.

  • main criteria
  • select Invalid error when buying

main selection criteria

Thus, we consider how to choose the most important device parameters for the protection of the wiring in the house,apartment.Photo producers of switching devices

  1. short-circuit current.To select the circuit breaker short-circuit current, should be considered an important condition - the rules of the SAE machines with maximum breaking capacity of less than 6 kA prohibited.Today, devices may have three ratings;4.5;6 and 10 kA.If your house is located next to the transformer substation, select the circuit breaker is triggered by a short circuit in the limit of 10 kA.In other cases it is enough to choose the switchboard nominal value of 6,000 Amer.Marking automation
  2. Rated current (working).The next, equally important criterion for choosing machine for home - for the rated current.This feature displays the current value above which will disconnect the circuit and thus protecting the wiring against overloads.To select a suitable value (which may be 10, 16, 32, 40A, etc.), it is necessary to rely on the cross section of the cable wiring and home power consumers.That is how much current can skip through the veins themselves and at the same time, what the total capacity of all household appliances, will depend on the switching device operating current.In this case, to select the appropriate characteristics of the circuit breaker recommend that you first determine the section of the cable in your house or apartment, and then follow the data tables:
  3. Tripping current.At the same time a working machine current need to pick up its nominal current operation.As you know, when the high-power electrical inrush current can be significantly higher than the nominal (up to 12 times the value).To the circuit breaker is not tripped by taking the inclusion of the engine, as a short circuit, the class need to choose switching device.Today, for domestic use can be used by classes B, C and D. For houses and apartments the best choice for a Class B device, if installed in the kitchen stove and no major power consumers.If you have installed a powerful electric or electric boiler, it is better to choose the right machine class C. So if you are involved in a private house of high power electric motors, it is necessary to carry out selection of the switching device marked «D».
  4. selectivity.This term implies a shutdown in an emergency only certain, the problem area, not all electricity in the house.There is already a need a little insight into the logical chain and choose the denomination of circuit breakers according to the serving line.The top of the so-called branch should take an introductory machine, the denomination of which does not exceed the maximum permissible load on the wiring, based on the section of the wire.Rated current introductory switching device must be greater than the operating current value of all the other lower-level circuit breakers in the panel.For private homes it is recommended to select the input device to 40A, on the electric stove - 32A, on the electrical up to 5 kW - 25A socket - 16A and lighting - 10A.If you select this option the electrical panel assembly selectivity condition is satisfied.Example selectivity
  5. number of poles.Another no less important selection criterion, which typically occurs less likely questions.So, for the single-phase 220 V input it is recommended to choose a two-pole single-phase machine.On lighting and individually connected appliances (eg, washing machine, water heater, air conditioner) is necessary to find a suitable single-pole circuit breaker.If you are in the house three-phase mains on the input buy four-pole switching device.And to protect the motor from overcurrent select the three-pole machine at 380 volts.Different number of poles
  6. manufacturer.It is important to choose a company machine, or when buying a fake is not the fact that the parameters for the aforementioned facts are the same.As a result, at a current of short-circuit electromagnetic release may not work, and as a consequence - a fire in the house.To this did not happen it is recommended to carry out the selection of switching devices and other automation only on high-quality companies.Ranking of the best manufacturers of circuit breakers, we have provided in the corresponding article!Manufacturers of electrical goods

Worth also view the video instructions, which provided all the necessary tables and formulas to select the circuit breaker current, power, and cable cross-section:

How to choose a suitable nominal switching device for houses and apartments?
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listed the criteria for selecting the circuit breaker are major, and first of all pay attention to these parameters.It should be noted that to save on vending machines is very stupid!The difference between a quality product (from the manufacturer ABB or Schneider Electric) and counterfeiting is not too high, given that at stake is your home and, what is more important - life!

Unacceptable mistakes when buying

There are some errors that can prevent the electrical novice when choosing a circuit breaker on the power and load current.If you select the wrong protective automation, even a little "Overshot" rated, it can lead to many adverse effects: operation of the machine when the appliance wiring will not sustain the load current, the term switch services quickly reduced, etc.

To this did not happen, we recommend that you read the following errors, which will allow in the future to choose a circuit breaker for your house or apartment:
  • First guided not to power home appliances, andon the wiring.It is not necessary to carry out selection of the machine only on the characteristics of appliances, if the old wiring.The danger is that if, for example, to protect the electric stove you select the model 32A, a cross section of an old aluminum cable can withstand only the current in 10A, your entry will not stand and quickly melt, which would cause a short circuit in the network.If you need to choose a powerful switchboard for protection, first of all replace the wiring in an apartment with a new, more powerful.
  • If, for example, when calculating the appropriate denomination machine for the operating current you have left the average value between the two properties - 13,9A (not 10 and 16A), give preference to a larger value only if you know that the wiringsustain current load to 16A.
  • For garden and garage is better to choose a circuit breaker is more powerful, becauseHere the welding machine, powerful submersible pump can be used, induction motor, etc.It is better to foresee the connection of high-power consumers, so you do not overpay in the purchase of the switching device with higher ratings.As a rule, 40A is enough to protect the line in household conditions of use.
  • It is advisable to choose the entire automation from a single, high-quality products.In this case, the probability of a mismatch is minimized.
  • buy goods only in specialty stores, and even better - the official distributor.In this case you can hardly select forgery and in addition, the cost of products in direct supplier, usually slightly lower than mediators.

way to understand the original you buy cheap or fake, you must visually inspect the machine, as shown in the video:

How quickly distinguish a fake?
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That's the whole technique of correct choice of machine for their own homes, apartments and villas!We hope that now you know how to select the circuit breaker current, load and others, no less important characteristics and what mistakes should be avoided when buying!


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