Class of accuracy in electrical measurements in series with the load, so the same current flows through the load and the ammeter. The voltmeter is used in parallel with the load, so the voltage between the two terminals of the load is equal to the voltage between the two terminals of the voltmeter. Ideally the measuring device should not affect the circuit parameters i.e., the internal impedance of the ammeter should be zero (no voltage drop over the ammeter) and the internal impedance of the voltmeter should be infinite (no current through the voltmeter). However, in actual case, ammeters have a low but non zero impedance
Electrical contractor classified by three major types of work performed. Electrical contractors employ workers in many capacities, determined by their level of training and experience. Some common jobs include: In the United Kingdom, the two main trade associations are the Electrical Contractors' Association, covering England, Northern Ireland and Wales, and SELECT - the Electrical Contractors' Association for Scotland. The main certification bodies are the National Inspection Council for Electrical Installation Contracting and Elecsa. The National Electrical Contractors Association (NECA) is the largest trade association in the electrical contracting industry, with about 4500 members. NECA publishes an industry magazine, and sponsors an annual