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§ 9 Verification of meters

This information is more for general development. Each meter has a so-called intertesting interval (MPI), through which theoretically an inspector of power inspection should come to you and check the correctness of its switching on and accuracy of measurement. I will not lie, I will not say for sure, but it seems to be 5 years for induction meters, for electronic ones it is -10. At your home where in the farthest box must be the passport of the counter in which the date of the next verification should be indicated. Do not look at the verification interval specified in the passport - some very smart manufacturers to show what they have good counters, overestimate this interval. This interval is not exactly determined by the manufacturers. And it is precisely in your interest that everything was at its best at this date - the seals, the correctness of the connection, and all kinds of left wires did not enter the apartment. If there are no seals, roll up to the ZhEKovsky electrician for sure. Type was an emergency situation, he broke the seals and put his own - this is not forbidden. Of course, after the breakdown, supervision should be notified, but there is such a mess that no one will know for sure whether anyone was called or not. Them and on an emergency call you will not be formed.
If they do not come after the end of the verification period, it is not a sin to go away yourself. The explanation could be something like this: "The term of the test verification has come out and now your meter doesn’t know what it counts - maybe electricity, and maybe wind speed in Antarctica. Therefore, until calibration is done, I will not pay for electricity." It's kind of like with a car: no technical inspection - you can't drive. And any court will be on your side. An untested counter is considered defective.

Calibration of meters at the installation site is always carried out without measuring transformers to which the meter is connected. For this, exemplary devices are included in the secondary circuits of current transformers and voltage transformers. Verification can be performed either by the method of wattmeter and stopwatch, or by the method of comparison with the model counter.
The use of a model counter is always preferable, since in this case the fluctuations of the load do not affect the results of verification. However, almost always the wattmeter and stopwatch method is used as more accessible (portable model counters are not produced in our country). Before checking, depending on the accuracy class of the meter being tested, the instrument should be selected according to the accuracy class. According to the basic requirement of GOST 14767-69, exemplary devices must provide electricity measurement with an error not exceeding 1/4 of the permissible error of the meter being checked. So, for class 2.0 meters, the error in determining the electricity should be no more than 0.5%. It should be remembered that this error is the resultant error of all model instruments that measure energy, that is, one or two watt meters and a stopwatch.

In life, it all looks like this: an exemplary wattmeter is connected, or an ammeter with a voltmeter, an exemplary load is connected and the current power for a certain period is measured. That is, simply put, the number of disk revolutions (or pulses for electronic) at a certain standard current and voltage applied to the counter over time is considered. Coincidence number - fit, not match - in the laboratory ...

PS Finally, I will tell one funny story (real) from life. My friend had a dacha and there was a power line next to it. But officially he was not connected to it. Either he was lazy to run about the connection, or the limits on the installed capacity were over and therefore were not allowed to connect. In short, this moment is dark and lost in the historical darkness.
Well, he, without hesitation, dug a trench to the nearest post, put a cable into it, picked it up and connected. Well on the catcher and the beast runs. That's right here checking and catch him as they say in the act. The cable is cut to the root of the pillar and taken away. And after a while the claim comes to him - pay dear comrade electricity for six months at the rate of 1.5 kW every hour and around the clock.
I do not remember exactly how much, but the amount was decent. Well, my offender and says: "Well, I will pay for the energy, if you deduct the cost of my cable cut." The power engineers immediately sang with righteous anger and said: "But haven't you become a brazen guy at all?"
It came to court. Power engineers flatly refused to recognize the fact of cutting the cable, and indeed its presence on the pole. A friend says: "Well, since there was never a cable, how could I even steal electricity?"
The court won, did not pay any fines, used electricity for half a year for free. Losses: 5 m cable. True, then with the official connection, he had big, very big problems, but that's another story ...