How to pay for light less without changing the way of life.
Every year the price for used electricity becomes more and more. It's time to think about how to save money on this service, and it's not necessary to use illegal methods. Installing in your house a multi-tariff electricity meter you can no longer think about an extra outlet, included in the network. It takes very little time to document and install such an accounting device, and you can buy it at an electronics store, or on special websites on the Internet. 
At the moment there are three tariff systems for payment of power supply services:
- first - payments are made at a single tariff, regardless of the time of day;
- second - from 7.00 to 23.00 pay the usual cost, and the rest of the time by 30% less( two-rate system);
- the third one is a three-tariff one, when the day cost 1 kWh is standard, at night - 70% lower, and only at peak hours: from 07.00 to 10.00 and from 20.00 to 23.00 - the cost increases by 70% from the usual.
It is necessary to get used to washing at night and try not to use household appliances during peak hours. The installation of three-tariff electricity meters is a mutually beneficial transaction, because at night the load on the network is sharply reduced, and in the daytime it increases again, and this leads to voltage drops and premature aging of the station equipment. 
How to take readings from a three-tariff meter.
Almost all models of three-tariff meters( including the promoted Mercury brand) display the following indicators on their liquid crystal display:
- the numerical value of active and reactive electricity for all four tariffs and the total capacity;
- current strength and voltage value in each phase;
- active, reactive and full power consumption;
- for the last three months the maximum power in the peak period;
- common phase power factor and separately for each phase
- phase angle;
- frequency of current in the network;
- number, month, year, and current time.
The additional technical capabilities of the three-rate electricity meters include:
- A log for recording events in which the time is fixed:
- when the counter has been disconnected;
- breaks or turns off one of the phases;
- device opening;
- time correction;
- overrun of electricity depending on the time of day.
- Ability to set the time interval for daytime and night time.
- Voltage and frequency variations of current;
- Possibility to connect a secondary power source.
In order to take readings from a three-rate meter you need to correctly enter them in the receipt for payment, follow the instructions:
- press "Enter" and record the readings of T1, after again - "Enter" - write T2 and again "Enter" - T3;
- from the received T1 we subtract this indicator for the last month, and multiply by the tariff for the peak time( morning and evening)
- tariff T2 - night tariff, we perform the same mathematical actions with this indicator, as well as with T1;
- T3 semi-peak time is the biggest tariff for paying for light;
- add up all the results obtained and take away the benefits, if any.
A "smart" three-tariff electricity meter will help if the receipt for the last month is lost, while holding down the "Enter" button for 2 seconds, we get, in turn, all the indicators. The model of the three-tariff electricity meter Mercury, like many others, has this function and stores data during the entire lifetime. 