In this day and age, you may not have a watch, but you must have an electric meter in your home. As a measuring instrument related to people's livelihood, the electricity meter is an essential tool for electricity metering and electricity bill settlement.
So have you carefully observed your own electricity meter? Are you using a traditional mechanical meter or a smart meter?
From the appearance of the electric energy meter, what kind of electric energy meter is the electric energy meter that meets the legal requirements?
The nameplate of the electric energy meter should contain at least the following information: name, model, serial number, accuracy level, constant of electric energy meter, reference frequency, reference voltage, reference current and maximum current, product standard code based on, manufacture Factory name or trademark, date of manufacture, unit of measure, number of decimal places or multiples of indicated value.
In addition, qualified electric meters shall also have the following identifications:
(1) The nameplate of the electric energy meter should have the national measurement and manufacturing license (CMC) logo and license number;
(2) The shell of the electric energy meter should be affixed with the verification certificate of the verification organization and marked with the validity period;
What does the content of the nameplate of the electric energy meter mean?
On the nameplate of the electric energy meter, we can see the following terms: single-phase, three-phase, active, reactive, etc. The nameplate is also marked with the registered model: such as DDS×××, the first D stands for "electric energy meter", the second D stands for "single-phase", and S is the prefix of "static type (commonly known as electronic type)" in English. . "×××" represents different meters produced by different enterprises.
In my country, the voltage system of 220V is adopted, and the frequency of alternating current is 50Hz. Special attention should be paid to the marked current range: for example, 5(20)A means that the basic current is 5A and the maximum current is 20A.
The nameplate is also marked with a sign of ① or ②, ① means the accuracy of the electric energy meter is 1%, or a class 1 meter; ② means the accuracy of the electric energy meter is 2%, or a class 2 meter.
Why does a red light keep flashing when the energy meter is in use?
There will be a red indicator light on each meter - the pulse light, the pulse indicator of the meter will flash when electricity is being used. "1600imp/kWh" marked on the meter nameplate is the pulse constant. The pulse constant is the number of pulses per kWh, which means that the customer consumes 1 kWh of electricity, and the pulse light flashes 1600 times.
The flashing frequency of the pulse light varies with the power load. The greater the power load, the faster the power consumption will naturally be, and the faster the pulse light will flash.
How to understand the current specification of the energy meter?
The capacity of the electric energy meter is represented by the maximum current. For example, the parameter of a certain type of electric energy meter is 220V, 5(20)A, which means that the rated voltage of the electric energy meter is 220V, the basic current is 5A, and the rated maximum current is 20A. If the load exceeds the maximum current of the electric energy meter, the electric energy meter may burn out or even cause a fire.
Why do electric energy meters rotate on a periodic basis?
With the prolongation of the use time of the electric energy meter, the mechanical wear or the aging of the electronic components will occur, which often causes the measurement error to exceed the international allowable error limit. In order to ensure the measurement accuracy of the electric energy meter, the electric energy meter needs to be removed for periodic verification according to the relevant provisions of the state.
Do smart meters go faster than mechanical meters?
Smart meters are more sensitive than mechanical meters. Using electrical appliances of several watts or even a few tenths of watts, traditional energy meters turn extremely slowly or do not rotate at all, but smart meters can measure accurately, and any small current will make the meter rotate.
In addition, traditional electricity meters are usually "inductive electricity meters" in which a disc rotates with electricity consumption. The disc is supported by a bearing. Over time, the bearing gradually ages, friction increases, and the rotation speed becomes slower, paying more than the actual use. With less power, smart meters won't have that.