In this part we consider more tools which will be useful for any general purpose job around the house or in your garage. But primarily we will devote more attention on some of the basic precautions needed to work with or handle electrical circuits.
- Spanners or Wrenches– They come in all sizes and shapes. The most versatile and the most abused spanner is the Adjustable Wrench. As we have said many times, always exercise caution in using them. Apply force only in the direction of the fixed jaw and not in the direction of the movable jaw. A movable joint takes a lot of punishment and eventually the grip loosens. If the nut or bolt slips, you run the risk of injury as well. Alternatively, any undue force applied can wreck the bolt or its head. Another type to work with pipes and pipe fittings comes with serrated jaws is called as Pipe wrench. Look for prime quality drop forged wrenches for long life – both for self and for the tools.
Fixed Wrenches are available in many forms too – Open ended, combination or socket types ( box spanners). Ideally box spanners enable the application of maximum force with minimum damage. Buy a set of spanners – with various sizes.
2 . Line Tester – A small screwdriver which has a built in neon bulb that lights up when the tip comes in contact with a live wire. You must touch the back end of the tester while testing for live wire. That provides the return path to the neon bulb’s electric circuit. This tester is the basic tool to identify the live wire when you are working with mains supply.
Working with mains electricity:
When working with mains supply it is essential to be highly cautious. A normal household supply in the US is 110 Volts while in Europe it is 220 Volts. The higher the voltage the higher is the possibility of passing higher currents. “It is the mills that kills and volts that jolts” goes an old saying about electricity. The mills here represent the milli amperes. Ampere is the unit of current. As low as 8 milliampere can result in fatality when it passes through our body.
In a dry environment, most individuals exhibit skin resistance of around 100 K Ohms. Ohms is the unit of resistance. However, when the skin is in contact with moisture or liquid, the resistance drops to less than a few K Ohms, which will allow dangerous currents to pass through bodies. This is one of the main reasons why restrooms and bathrooms are veritable death traps when you come in contact with the mains supply.
Always turn off the power supply before you undertake any repair. When you are rigging up power to outside the house, use a suitably rated 1:1 isolation transformer for better safety. Normally a household mains supply is configured with a live (Red wire) and a neutral (black wire) between which there exists a 110 Volts potential difference. The neutral connection is referenced to the ground and hence anyone touching a live wire standing on the ground poses the fatal return path to the mains supply. Adding an isolation transformer makes the electrical supply floating without any reference to the ground. Next time when you rig up the outdoor Christmas lightings, add an adequately rated isolation transformer.
Most households these days invest in residual current circuit breaker or residual current device or Ground fault Circuit Interrupter or Earth leakage circuit breaker – which all refer to the device which trips the power supply when there is a residual leakage current from a faulty appliance. These devices trip the power supply within a few milliseconds. Still it is prudent not to depend on them always when you draw power to exposed regions outside the house.
Disclaimer: This series of articles contains general information on home maintenance of household machinery. This is not an exhaustive list of service procedures. A lay user can only attend to general maintenance with limited skills and tools. All electrical and electronic machines operate at lethal voltages and can CAUSE serious damage or even electrocution or shock hazard to self and home. It is positively dangerous to even attempt to repair any electrical machine without the required skills or knowledge. Always refer servicing to qualified technicians or the dealer. For detailed troubleshooting, refer to owner’s manual and service manual if available. The information contained herein is only for general reference and does not carry any warranty implied or otherwise. You use the information provided here at your own risk.