Household appliances

• SMART technology


  Self Monitoring Analysis and Reporting Technology
• CONTRIBUTION OF TECHNOLOGY TO HOME MANAGEMENT

  Workload reduced - laundry (washing machine), food prep (mixer, processor)

  Time saved - microwave cooking time

  Security - gates, cameras, alarms

  Management - pay bills, banking
• SELECTION OF HOUSEHOLD APPLIANCES

  cost - shop around, initial and running costs, energy

  brand- more expensive = more reliable so cheaper in long run

  safety - British kitemark

  size - space available (single door fridge vs double)

  Ease of cleaning - self cleaning oven

  guarantee
• electrical appliances


  with motor - food processor

  with heating element - kettle

  refrigeration appliances - standard fridge

  other - microwave
• kettle design and construction

  made of stainless steel, chrome, plastic, tempered glass

  Dome or jug shaped
• parts of kettle


  Lid - filling

  Spout & filter -remove limescale

  Vent - allow steam to escape

  Heat resistant handle, Water level indicator, On-off switch, Power light on, Electric element, Thermostat, Lead & plug
• working principle of kettle

  Kettle turned on, electricity flows through element

  element offers resistance causing it to heat

  Water heated by conduction and convection currents

  When water boils thermostat switches off electricity

  Boil dry device automatically switches kettle off if no water present
• guidelines for use


  Follow manufacturers instructions / advice,

  use dry hands - no electrocution risk

  Do not overfill - water will bubble out and you could scald yourself

  Allow to cool before refilling
• design of fridge


  Outer casing of enamelled steel

  Internal lining of moulded polystyrene

  Insulating material between inner & outer layers

  Magnetic door, rubber gasket which forms seal

  Adjustable, plastic coated shelves
• MODERN FEATURES of fridge

  ice/water dispenser, auto-defrost
• working principle of fridge


  Compressor at base of fridge contains gaseous refrigerant (freon 12)

  Motor forces gas into condenser

  Condenser converts to liquid

  Liquid refrigerant passes to evaporator, draws heat from fridge changes to a gas

  Gas returns to compressor, cycle begins again

  Thermostat disconnects motor when temperature is between 1ºand 4ºC and reconnects when temperature begins to rise
• guidelines for use fridge


  Cover to avoid foods drying out & cross-flavouring

  Store raw meat below cooked - lowest part of fridge and not beside food that it could contaminate

  Avoid opening cool foods before placing in fridge
• microwave working principle


  Microwaves (electromagnetic waves) produced by magnetron in oven

  Energy waves attracted to water & fat (energy is absorbed)

  Enter food and cause molecules to vibrate causing friction

  Friction produces heat in food

  Food cooked by conduction
• microwave -ELECTROMAGNETIC WAVES(PROPERTIES)

  Reflected - metals

  Transmitted - pass through (glass, plastic)

  Absorbed - water, fat, sugar
• design and construction of microwave

  Metal lined box, enamel interior

  Glass door with perforated metal layer

  Seal & safety lock

  Control panel- digital/dial

  Light

  Flex & plug
• Magnetron


  converts electricity to electromagnetic energy
• transformer


  increases voltage
• Wave guide


  distributes microwaves
• Turntable


  even cooking of food
• suitable uses for microwave

  Cooking - eg popcorn

  Reheating - eg soup

  Defrost - eg frozen food

  Melting - eg chocolate

  Hot drinks - eg milk
• unsuitable uses of microwave

  Baking - will not brown

  Roasting - will not brown

  Foods with high fat

  Content - high fate, high level heat burn quickly,

  Large quantities of food - take longer than individual portions
• guidelines for use of microwave

  do not touch plug with wet hands

  No metal or metal trimmed containers may be used because electromagnetic waves will be reflected

  Stop midway through cooking and stir to avoid cold spots and food poisoning