One of the main characteristics of any lamp is its power. Its luminosity also depends on it, especially it concerns glow lamps. Knowing the power consumption of lamp, it is possible to calculate the general energy consumption of lighting system of the apartment or office.
It is required to you
- tester, wattmeter, voltmeter, ampermeter
Instruction
1. On the majority of lamps their power consumption and rated voltage with which the lamp works is specified. For example, if on lamp 220 V and 60 W are written, it means that at inclusion in network with voltage of 220 V its power will be equal to 60 W. It is the maximum power which this lamp can give.
2. If the power of lamp is not specified on it or it works in network with tension below rated (if tension is higher than rated, to happen short circuit, and it will just burn down), measure its power independently. Attach tester in the wattmeter mode parallel to lamp, connect it to current source, it will show its power. In the absence of wattmeter the power of the working lamp can be calculated independently. For this purpose attach lamp to current source. Consistently attach the ampermeter to it, and in parallel the voltmeter. Having closed lamp on current source, take readings of current intensity from the ampermeter in amperes, and tension from the voltmeter in volts. For same it is possible to use normal tester, only for strain measurement attach it parallel to lamp, and current intensity - it is consecutive. Find the work of current intensity on tension. Lamp power in watts will be result.
3. If lamp resistance is known, then it is enough to measure only the current intensity or tension by means of tester. If tension is measured, then for determination of power of lamp square its value and divide into value of resistance: P=U²/R. If current intensity is known, then for calculation of power find the work of square of current intensity and value of resistance: P=I²\• R. At measurement of strain and current intensity on DC power source surely consider polarity of measuring tools that they have not deteriorated. Connection of devices you make connection of devices at the disconnected current source.