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The voltage in a private house is 160 - 180 volts. What to do?
Low network voltage is a problem typical for households in the private sector. 160-180 volts - this voltage is not enough for most household appliances and fixtures. Even the simplest incandescent lamp at an excessively low voltage no longer shines, but simply “denotes” its filament with a soft crimson color.
First of all, it should be remembered that the electricity supplier must ensure the quality of this electricity at the input, that is, at the border of responsibility between the subscriber and the supplier. In fact, the boundary of responsibility is most often located at the point of connection of the OHL branch to a private house.
Therefore, the question of fundamental importance is: within whose area of responsibility is the problem? If the voltage on the overhead line itself is as low, then the energy supplying organization is responsible for this (gardening board, Energosbyt, etc.) But if the voltage there is in order, then the input is the problem area, and this is already on the consumer’s conscience.
It is practically not at all easy to make measurements on the overhead line support at the branch connection point, and it is also unsafe. Such work can only be done by qualified employees of the electricity supplier organization.
For example, if only you have voltage problems, and the neighbors connected to your own phase do not experience any inconvenience, then this clearly indicates that the technical problem is on your branch.
Another characteristic sign of problems precisely at your input may be the lack of subsidence before the inclusion of any electrical appliances in your home. That is, if the input device is turned off - the input voltage is full, and if the stove, kettle and vacuum cleaner are working at the same time, then they can’t practically work, as the drawdown is obvious and noticeable even without the use of special devices.
Sagging within the homeowner's liability boundary
If the voltage drop occurs precisely on your branch, then the following options are likely:
1. The cross section of the lead-in conductor is not sufficient for the available length. On too thin conductors, a voltage drop occurs, which in the case of ultimate load can be very significant.
2. The branch circuit has bad contact, which plays the role of additional resistance. On this resistance, in accordance with Ohm's law, a voltage drop occurs. These volts, “disappearing” due to poor contact, may not be enough.
Lost volts cause heat to be generated. In the first embodiment, this is not so critical, since the lead-in conductor is heated uniformly along the entire length. But with the second option, bad contact will warm up. And very intensively, up to the point that the place of heating will be visible to the naked eye. Heating will contribute to further deterioration of the contact, and the result will be either a complete inoperability of the input, or, in the worst case, a fire.
If you find out that the voltage drop in the house is caused by problems in your power line branch, then the following actions should be taken:
1. Critically assess the status of contacts. This, first of all, concerns the junction of the main power line and your branch. How is this connection made? If using ordinary twisting, then it is very likely that the problem lies here: the transition resistance of such a contact located in the open air is growing steadily, and only practically ideal cooling conditions save from fire. All this is especially true if the aluminum main and copper branch conductors are connected by twisting. Unfortunately, this also happens.
If the branch is made using certified clamps, then it is necessary to pay attention to the condition of the housings of these clamps. Reflow and other damage to the clamp housing may indicate a problem with electrical contact. You can verify the existence of these problems by turning on the maximum load on the network (as many power consumers as possible) and making simple observations. If sparking occurs inside the clamp, smoke is emitted, and the temperature clearly rises, then the clamp is uniquely the cause of voltage subsidence and must be replaced.
2. Another place of problem contact may be the upper terminals of the input switching device (most often the machine). In this case, sparking can come directly from the input shield, and the case of the circuit breaker will have signs of fusion. Then the input device must be replaced.
Sagging voltage within the energy company’s liability
At first glance, this case seems to be the simplest: they cooperated with neighbors, wrote a complaint - and please. The supplier is required to ensure the quality of the electricity supplied by law.
However, in fact, everything is much more complicated. Undervoltage in the power line network can be associated with such circumstances:
1. transformer substation overload,
2. the lack of cross-section of the conductors of power lines,
3. “skew”, that is, uneven loading of the phases of the transformer.
The first two reasons are not difficult to diagnose, but not easy to eliminate: either the replacement of the transformer or reconstruction of the power transmission line is required. In addition, the network load is not stable, which means that with the third reason, too, not everything is clear. It should be noted here that today at most substations relay protection is working properly. And this means that the voltage drop due to banal overload is characteristic only for some gardening and deaf settlements.
Justification that the power of the transformer is insufficient, or that the load is distributed unevenly across the phases, will be virtually impossible to find. Now there is an overload or skew, and after half an hour it may already be gone. Accordingly, the voltage drop is also unstable, and consumers are left alone with their problem.
Of course, it is necessary to write “paper” to energy salesmen in a similar situation. But you still have to take some steps yourself. Alternatively, in such a case, you can obtain permission from the sales company and bring it into the house all three phases. Next, you can install an automatic phase switch at the input and always use only the phase that is least loaded at the moment, the voltage in which will be close to 220 volts.
In the absence of such permission from Energosbyt, it is possible to carry out a periodic “phase change” with the participation of electricians from the operating organization, who will provide the necessary shutdown at the substation. But it should be noted that such actions will hardly radically solve the issue.
The insufficiency of the cross-section of the conductors of power lines relatively often causes a voltage drop, not only in garden gardens, but also in the private sector within the city. The fact is that a couple of decades ago, these lines were carried out by the cheapest wires. The most common were steel-aluminum wires with a cross section of 16 square meters. mm Steel provides this wire with increased bearing capacity, but significantly reduces conductivity. And this despite the fact that the cross section is 16 square meters. mm so it’s not particularly large, and aluminum itself is not very conductive.
At that historical stage, when even an electric stove was not available in every private house, and there were no other powerful electric receivers at home, there was quite a power line from the AC-16 wires. And today, on the site of the former small houses, whole palaces are being built. Moreover, preference is increasingly given to electric boiler heating. Of course, electricity consumption increases significantly.And even if the transformer at the substation copes, or it was replaced, then on thin wires at high currents there is a significant voltage drop.
A characteristic sign of insufficient cross-section of the power transmission line wires or substation transformer power is normal voltage at night and constant subsidence in the evening. But it is worth noting that these two problems often "go hand in hand."
Where there are weak power line wires - there is also a low-power transformer. And the need to make large investments hinders the elimination of problems. One transformer costs about a million rubles, depending on its capacity. In addition, the reconstruction of power lines using SIP also "will cost a pretty penny."
For these reasons, energy retail companies, gardening and village administrations can remain silent for years, even if there are obvious problems.
Known methods of private solutions to the problem of low voltage in the network:
1. Installation on your own input voltage stabilizer. To be honest, this measure in the case of a drawdown of up to 160-180 volts is doubtful. Firstly, the stabilizer of such a deep stabilization and suitable for home ownership power will be very expensive. And secondly - a dozen of such stabilizers in the power line network - and the network literally falls to its knees, from where it can no longer be lifted by any stabilizer.
2. Installation of step-up voltage transformers at the input. This also does not fit at all. Suppose we put a transformer, selecting a transformation ratio from 160 to 220 volts. And in the morning the voltage in the network returned to normal, and instead of 220 in the sockets it became 300 volts. All appliances and bulbs burn out. After all, the problem with the voltage drawdown is that this drawdown is almost never stable.
3. Installing an additional grounding device at the input. Of course, to the zero working conductor. The meaning here is that the power line is a direct conductor (phase) and a reverse (zero). The cross section may be insufficient for both, but by grounding the neutral conductor, you can reduce the resistance of the working zero and in general, the resistance of the line will also decrease. However, such a measure is also fraught. First of all, by the fact that during repairs at any point on the line, electricians can mistake places zero and phase.
In this case, the grounded phase will cause a short circuit. Another option is to break the working zero on the power line. Then all operating currents will go through your grounding device, which can lead to difficult to predict results. In the best case, the grounding device will simply fail.
As a result, it will have to be recognized that there is no independent radical solution to the problem of voltage drop due to a weak substation transformer or too thin transmission lines wires. One in the field is not a warrior. It is necessary to unite with neighbors, make an appeal to the energy sales organization and be prepared for the fact that part of the costs will have to be borne. Otherwise, the matter may drag on indefinitely.
Alexander Molokov
See also at bgv.electricianexp.com
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