Calculation of power consumption is most often made for the bodies working from electric energy. The maximum power power is called rated and is specified on the consumer or in technical documentation on him. If the device works not in the nominal mode, power consumption can be calculated independently.
It is required to you
- - tester;
- - caliper;
- - ruler.
Instruction
1. Attentively examine the device or technical documentation to it. On it the rated voltage and rated power have to be specified. For example, if on a lamp 220 V, 100 W are written, it means that if to include such lamp in standard household network in which tension is 220 V the power consumption of a lamp will be equal to 100 W.
2. When one of these parameters is unknown, connect the device in network and by means of a tester find force of the current proceeding on it and tension at which it works. For this purpose adjust a tester for work in the ampermeter mode. Attach it to the consumer consistently. If the device works at a direct current, surely consider polarity of its accession. Take its readings, having measured current in amperes.
3. After that switch a tester for work in the mode of the voltmeter and attach it, observing polarity in a case with a direct current, parallel to the device. Take readings of a tester in volts. To find power consumption, increase value of tension by P=U•I. current
4. If the device resistance which is shown in documentation or is measured by an ohmmeter under which it is possible to adjust a tester is known. That measure only the current or tension. Then power consumption will be equal to the work of a square of current on P resistance = to I \to U-00B2 \• R. And if to measure tension, then determine the power consumption as tension square relation to resistance of the consumer of P=U²/R.
5. Determine the power of the electric motor by its dimensions. For this purpose measure diameter of the core, its length and synchronous frequency of rotation, recognize polar division of the engine, and by it, by means of the special table an engine constant an engine constant. Calculate power consumption, having increased an engine constant by diameter of the core in a square, length and synchronous frequency of rotation. Increase result by 10 (^-6) (P = C•D ²\• l· n·10^ (-6)). The received power will be in kW.