Personal Safety for electrical installations

It’s never a mistake to read the basics again.

  • Avoid contact with energized electrical circuits
  • Treat all electrical devices as if they are live or energized
  • Disconnect the power source before servicing or repairing electrical equipment
  • Use only tools and equipment with non-conducting handles when working on electrical devices
  • Never use metallic pencils or rulers, or wear rings or metal watchbands when working with electrical equipment
  • If it is necessary to handle equipment that is plugged in, be sure hands are dry and, when possible, wear nonconductive gloves, protective clothes and shoes with insulated soles
  • If it is safe to do so, work with only one hand, keeping the other hand at your side or in your pocket, away from all conductive material
  • Never touch another person’s equipment or electrical control devices unless you are instructed to do so
  • Enclose all electric contacts and conductors so that no one can accidentally come into contact with them
  • Never handle electrical equipment when hands, feet, or body are wet or when standing on a wet floor
  • When it is necessary to touch electrical equipment (for example, when checking for overheating), use the back of the hand. Thus, if accidental shock were to cause muscular contraction, you would not “freeze” to the conductor.
  • Be aware that interlocks on equipment disconnect the high voltage source when a cabinet door is open but power for control circuits may remain on.
  • De-energize open experimental circuits and equipment to be left unattended.

What is the difference between technical loss and non-technical loss?

Technical losses are coming from current flowing in electrical installations. They can not be avoided, but reduced by proper installation. Technical losses can be calculated.

  • Losses due to conductor resistance
  • Losses due to induction of electromagnetic fields
  • Dielectric losses due to insulation material between the conductors
  • Losses due to harmonic distorsion
  • Losses due to poor earthing

Non-technical losses are more difficult to reduce. 

  • Meter tampering 
  • Hooking or bypassing the meter
  • Wrong programmed instrument transformer ratios in the meter
  • Burden for instrument transformers too high
  • Wrong meter readings
  • Meter is faulty or out of accuracy class
  • Unpaid electricity bills

Non-technical losses are more difficult to reduce. For the technical debugging on-site test equipment can solve many cases. For customer which don’t pay their bills, prepayment meters can be installed.