Throughout this post, references are made to meters and their use in continuity testing of individual parts of the appliances and their connecting wires. All testing and checking for ‘open’ (not allowing for current flow) or `closed’ circuit (allowing current to flow) must be carried out using a battery-powered multimeter or test meter. Testing should never be carried out on live items under any circumstances. Appliances must be disconnected from the mains supply. Read the rest of this entry »
There are two main types of shavers: fully portable (powered by batteries, either dry cell or nickel cadmium rechargeable), and mains powered which usually incorporate a variable voltage option switch (110-130 volts or 210-240 volts). Correct maintenance is essential if they are to work efficiently and have a long and useful life while simple care and cleaning will greatly improve their smooth operation and reduce the likelihood of recurrent breakdowns. Read the rest of this entry »
The domestic vacuum cleaner has been with us now for some 90 years, during which time it has become the most popular labour-saving appliance in the home. The basic principle of operation is quite simple. An electric motor drives fans to create a fast-moving air flow. At one end, a vacuum (suction) of air is created, while at the opposite end the air is exhausted. If the air is moved quickly enough at the inlet end, it will carry with it any debris that enters the airflow. A means of removing the debris from the airflow is required to prevent its redistribution as the air is expelled. Read the rest of this entry »
Many appliances usually powered by a mains electrical supply can now be obtained in cordless form. This means they are independent of the mains supply and powered by batteries housed within the unit. Greater flexibility of use has been given to a wide variety of equipment ranging from electric shavers to electric drills.
Small items, such as electric razors may be powered by ordinary dry cell batteries because their power consumption is low and operational time is relatively short. However, once dry cell batteries have run down, they need to be replaced. On larger appliances which are used for longer periods and for carrying out much more strenuous work, the need to renew batteries at short intervals would not only be expensive but extremely wasteful in terms of the materials used in their production. Many appliances now overcome this problem by using rechargeable batteries, which come in two versions. Read the rest of this entry »
