Power in an electric circuit is the rate of flow of energy past a given point of the circuit. In alternating current circuits, energy storage elements such as inductors and capacitors may result in periodic reversals of the direction of energy flow.
The portion of power that, averaged over a complete cycle of the AC waveform, results in net transfer of energy in one direction is known as active power (sometimes also called real power).
The portion of power due to stored energy, which returns to the source in each cycle, is known as reactive power.Źródło: https://en.wikipedia.org/wiki/AC_power
Maintenance-free parking systems
Actually, more rarely we encounter a situation where the parking lot waiting for us the person collecting the fee for parking and issuing the appropriate tickets. Commonly used are now automated systems that allow you to dispense with the employment service in the parking lot. Customers themselves, usually using the touch panel choose certain options standstill. After driving into the parking traveled with him it is possible only upon payment of the appropriate fees and scanned the ticket. Parking systems are designed so that the most common problems that may arise during their lifetime the irregularities in the electricity and then the appropriate repair must address electrician.
Automatic garage doorsIncreasingly, repair of electrical installations applies to problems with the installation, which allows the automatic opening and closing of the gate, for example, when entering the garage and so on.
Such solutions are becoming more common due to its convenience and therefore need to repair this type of installation is becoming more common.
First of all, the problem can occur in drives to the gates, which may not respond to user requests or for example open instead of closed.
Systems control the opening and closing of gates and barriers are most commonly used in their construction, electrical components, so repair them must deal with the electrician..