There are numerous detection devices available and choosing the right one to protect a particular area isn’t always easy. There is a whole range of circumstances to take into account — the size of the room, what’s in it, even how it is constructed, as well as what’s outside or even across the road.
You may need one or more types of detectors in any one area — for example, there are bound to be doors and windows to protect as well as the room itself. There may also be very large areas of glass, such as a patio door, draughts or heating, which may make it difficult to site certain types of detectors, and you may have pets in the house which will mean careful positioning and directing of the detection pattern. Read the rest of this entry »
There are no specific British Standards for control panels (or alarm devices themselves), although elements of BS 4737 relate to features found in alarm equipment. This is likely to change with the introduction of European Standards which will, for the first time, require individual components to meet levels of performance and construction.
It is very important to understand how an alarm system is operated if false alarms are to be avoided. To reduce this risk, manufacturers have been making instructions easier to follow and many panels now incorporate a Liquid Crystal Display (LCD) giving plain English step- by-step instructions to guide users through the arming, resetting and disarming procedures. Read the rest of this entry »
If the heating element tests OK, you should next check all the electrical wiring from the dryer timer assembly, thermostats, and drive motor. Electrical wiring in a dryer becomes brittle and burned because of the excessive heat. To locate defects in the wiring, use a volt/ohmmeter to make continuity checks on wires that you suspect are faulty.
The problem of no heat in the gas dryer is much the same as the electric dryer, except that instead of checking for a possible defective heating element, you must check the gas ignition circuit. A sure and simple test is check voltage to the gas burner wiring harness. Read the rest of this entry »
A basic understanding of electricity is essential, even for those who do not intend to carry out any repairs or servicing of appliances. Ignorance is no protection against your own or someone else’s errors and oversights, whether with repairs, servicing or installation.
Power is supplied to an electricity substation at a very high voltage — 400,000 volts — in three-phase form. There it is converted, via a transformer, to 230 volt single-phase for distribution to our homes. In normal circumstances, current flows from the live supply of the substation’s transformer, through the electrical appliances used in the house and back via the neutral conductor (cable) to the substation transformer’s neutral pole (a closed loop). Read the rest of this entry »
Aschematic diagram of the internal workings of a pod-type thermostat. This type is used in appliances that have a variable temperature control. It consists of an oil-filled pod connected to the switch by a capillary tube. When the oil in the pod is heated or cooled, it expands or contracts in the tube and operates a diaphragm. The diaphragm acts on the switchgear thus breaking the circuit and in this instance, ‘making’ the other. The cooling oil contracts, pulling the switch the opposite way — back to its original position; the process repeats if temperatures change. Read the rest of this entry »
The humble kettle has been given a new image in recent years. Simple versions consisting of only a container with a heating element fixed inside are still available, but for many years the trend has been towards the automatic kettle that turns off once the water has boiled.
Some more recent models have been further improved with high-speed elements and spout filling. The latest jug version combines all the features of a modern kettle with the added feature of the handle’s being positioned on the side, so that the user avoids the steam when pouring.
As with irons, cable damage through wear and tear and misuse tends to be a common fault. Cordless kettles and jugs preempt this problem. They are similar to cordless irons in that they require a power base that has its own mains lead. When the cordless kettle is placed on its base, electrical contact is made to its heating element. The operation from then on is like any other automatic kettle. Read the rest of this entry »
