Voltage represents the relation of work which is spent by a system for movement of a charge, to the size of this charge. In city power supply networks three-phase networks are used. How to behave when got to the field of the torn-off wire and what can lead the wrong behavior to?
Voltage belongs to power characteristics of electric field. There is also other definition of the term: it is the work relation to the size of the charge moved on the conductor on a certain distance. Voltage unit of measure in the SI system is the volt "In". It is called so in honor of Alessandro Volt who for the first time in the world opened a galvanic cell and received current. Sometimes voltage is estimated as potential difference. For example, potential is equal in one point to 13 V, and in another – 10 V. Togda tension between points will be equally 13 – 10 = 3 V.
Records of tension in practice
Depending on what tension is applied in any given system, use any given designation. If voltage more than 1000 V, then use kV; if it is more than 1 million. In – MV, etc. gigavolts, nanovolts, microvolts.
Voltage is measured by voltmeters which are divided into millivoltmetra, voltmeters, kilovoltmeters, etc.
Three-phase networks
All power supply system of the planet is under construction on three-phase network. It bears two types of tension: linear and phase. The linear tension of network is tension between two conductors, and phase – between the conductor and a neutral wire or zero. Therefore when we connect loading according to the triangular scheme, linear tension becomes equal phase and when we connect loading according to the scheme "star", linear tension increases in a root from three times. From here such designations of three-phase network as 220/380 V or 127/220 V. The first indicates phase tension, and the second – on linear. For general idea about voltage sizes on various objects, we will bring them.
Tension on some objects
Tension between electrodes when remove the electrocardiogram, - 1-2 mV. The finger-type battery – 1.5 V. Phone line – 60 V. An electric eel – 650 V. The high-frequency television antenna – from 1 to 100 mV. Contacts of the tram line – 550 V. A storm cloud – 10 gigavolts.
Helpful advice: how to behave in the field of the torn-off wire?
When the torn-off wire concerns the earth, there can be step tension. Till a certain moment it is not really dangerous. Deadly it becomes only when the way of the movement of electricity in a human body changes. Step tension – tension of a step of one person. Legs represent contacts, and current moves on the closed chain a leg leg. It is a dangerous state, but not deadly as through heart there passes a scanty part of electricity. If current leads to uncontrollable reductions of muscles and people will fall, the way of passing of current will exchange and step tension will increase. It is a deadly situation. It cannot be allowed at all. For this purpose it is necessary to leave a dangerous zone quickly, but very small short steps as step tension in direct ratio to distance between contact points. But it is better to jump on one leg from a defeat zone.