I heat the house with electricity, it is convenient, there is no red tape with gas and firewood. But the big disadvantage of this energy is its price, if you do not live in Siberia and the cost of a kW of energy is not equal to the ruble. My kWh of energy is estimated at almost 3 rubles, although there is a GRES nearby that generates electricity for many regions.
In addition, the house is in a gardening partnership and the main line is shut down for the winter. This did not suit me, so last year I had to pull from the 16x2 SIP transformer cable to my house. The total length is 400 meters.
I immediately felt the advantage of this connection in the summer, there are no voltage dips, no one disconnects without your knowledge, in the winter I will be with electricity. I was happy about this until winter came and it was necessary to connect two heaters with a total power of 2 kW.
The voltage dropped from 230 volts to 215. And if you include a kettle and, for example, a vacuum cleaner in the load, then the voltage completely "flew away" to 195 V. What is already critical for my technology is heating the room. In addition, there are GOST 29322-2014, regulatory values in the electrical network:
Naturally, this situation did not suit me and I decided to find out why this is happening and how to solve the issue. But before, knowing from the school curriculum that any conductive material has its own resistance in the electrical circuit, I began to consider what resistance my aluminum cable 400 meters long has. Fortunately, there are many online calculators, here's what I got:
The load power was taken at 5 kW, this value will allow more or less equipment in the house to exist and work within the normal range. But as you can see, the calculated voltage dropped to less than 200 volts. Which is not enough. Therefore, I began to ask an electrician how to solve this problem.
Here's what he suggested:
- It is possible to stretch three phases from TP, and this is a fairly large financial investment. In addition, the chairman may not give the go-ahead, for any reason.
- Ground the neutral wire on three supports, through the reinforcement of the pillars, which will reduce the resistance of one of the wires in a two-core cable
- Carry out neutralization / grounding in the distribution board of the house.
If the first two options require payment of an electrician. That third option can be done independently. Spending only on additional materials. So I decided to do it, although I didn’t dare for a long time. After all, I am a plumber by profession. But, the eyes are afraid of the hands do.
Here's what I got, before interfering with the shield, it was something like this:
And after, merging zero with "ground" it turned out like this:
The phase wire is connected through a two-pole circuit breaker to the metering device. The zero wire, which came from the transformer substation through the bus, was zeroed in this way:
He hammered an iron square into the ground, to a depth of two meters, and a copper wire with a cross section of 10 mm was brought to it. Oh, and experts will eat me in the comments) I understand that this method of zeroing is wrong and I need to make a contour, but at a depth of one meter I already have water and there is contact with the "ground". You need to understand that this option is temporary in order to survive a couple of seasons when it comes to serious editing according to all the rules.
What did the grounding of the neutral wire near the house give? The issue with the resistance of one core of a four hundred meter cable has been removed. The resistance seemed to be halved. That immediately affected the voltage indicators in the house under load.
Your author is on Ya Zen. Mikhailov Victor