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Alexander Araktcheew wrote: > People, decide what you need grounding for! > If for what normal people understand by this, then without climbing in > a shield is indispensable. Unfortunately, a face shield will not always help. Based on the results of checks in our In 60% of high-rise buildings in the city, the switchboards are not grounded. This figure for the country even higher. > And if you also know how it is measured, then the battery will disappear completely. Grounding for heating is strictly prohibited_ Although the resistance may be quite adequate. -- Good bye, Sergey

Kirill Frolov wrote: > AA> People, decide what you need grounding for! > 1). In order to connect together the common wire of all devices. This is not right. Why, in this case, also connect to the ground electrode? > 2). So that it is (for this there is a tip with a 1M resistor). And this is complete bullshit. > AA> If for what normal people understand by this, then without climbing > AA> a shield is indispensable. > There is no grounding in the shield either. The fact that sometimes it’s not really the grounding in the shield, but the grounding of the problem Housing office. Grounding must be present, and its absence is a violation of the PTE and PTB. >As far as I understand, this is a grounded zero: > F1 ------ -- > Tr-tr F2 ------ -- -- > F3 ------------------- consumer > 0 --------+---------- > | > --- > - > > Am I right? Not really. The fact is that the resistance of the neutral wire, strictly speaking, is not regulated. When measuring, only the circuit resistance is checkedphase-zero, from which the short-circuit current for a given circuit is determined, which should be three times higher than the operating current of the fuse links. Those. the resistance of the phase-zero circuit is quite sufficient, at which The fuses will blow, not the wiring. In the case of grounding, the resistance of the conductor from the ground electrode is measured (i.e. a system of pins driven into the ground) to the grounded object (in this shield case). This resistance should be <= 0.1 Ohm. The use of a neutral wire at the same time for grounding is sometimes used (if its resistance matches), but there is another limitation - it must be copper (steel). The use of aluminum conductors for This is _categorically_ prohibited, due to its fusibility. > AA> And if you also know how it is measured, then the battery will disappear > AA> final. > Why is it not needed to ground the computer? Justify. > In my opinion it fits very well. This is prohibited. Imagine that in a 100-apartment residential building everyone will ground something thread to the battery. The heating system resistance is usually much greater than 0.1 ohm and it is quite possible for quite high potentials to arise between heating system and neutral wire. PS. Before I went on vacation, a ministerial brochure arrived withInstructing then TB. By the way, there was a case described where an electrician was killed because of this. There was a battery (leaking) under the switchboard, he stepped towards it touched it and began to open the shield with his hands... -- Good bye, Sergey