The power consumed by any given electric device is measured by a wattmeter. But each house master has it not. At its absence it is possible to measure other parameters of a chain which included the consumer, and then on the basis of these data to calculate the power consumed by it.
It is required to you
- One or two multimeters
- Electric meter
- Switch
Instruction
1. In most cases, the house master has only one multimeter which can be switched in turn to the mode of measurement of current, to the voltage measurement mode. In this case, in the beginning switch it to the voltage measurement mode, having correctly chosen a limit and a sort of current. Having connected a multimeter parallel to the deenergized consumer (if it eats a direct current - observing polarity), include its food then, having measured tension on it, remember or write down result. Power off loading.
2. Switch a multimeter to the mode of measurement of current, also correctly having chosen a limit and a sort of current. Connect it consistently with the consumer (at food its direct current - also observing polarity). If starting load current the worker, a zashuntiruyta considerably exceeds a multimeter the switch and close it. Include loading food. If a multimeter zashuntirovan the switch, after the consumer's exit to an operating mode open it. Read result then also remember or write down it. Power off loading.
3. If you have two multimeters, having included them as appropriate, it is possible to measure tension on loading and the current consumed by it at the same time. At the same time, working with the consumer whose starting current is exceeded considerably by the worker, also do not forget to shunt the multimeter playing an ampermeter role, the switch, disconnecting it only after an exit of load of an operating mode.
4. Having increased tension by current, calculate power.
5. If loading is calculated on food from lighting network, it is possible to measure the power consumed by it by means of the electric meter. Certainly, that counter which is located in a guard on a staircase will not suit you as to use it as the power measuring instrument, it should disconnect in the apartment everything other consumers, including the fridge that is extremely inconvenient. It is necessary to use the separate electric meter, and, not necessarily sealed up and undergone checking as it will not be used directly. Having included the consumer via the counter, count how many turns will be made by its disk for a certain period. Having looked on the front panel of the counter how many turns of a disk correspond to one kilowatt-hour, disconnect loading, and then calculate the power consumed by it by a formula: P=(n/N)/(t/60) where n is the measured quantity of turns, N is quantity of the turns corresponding to one kilowatt-hour, t is measurement duration in minutes.