Electrical Installation Safety Procedures: A Comprehensive Guide

Posted on May 3, 2024 in Technology

Questionnaire 6: Electrical Installation Safety

1. Operations for Installation and Electricity Appropriation

During installation or when electricity is appropriated, the following operations should be performed:

  • Open and visibly cut all sources of food.
  • Block or lock equipment in the open position, if possible, by cutting.

2. Five Rules for Prevention and Protection During Work Without Tension

  1. Open cut all visible sources of tension: Use switches and disconnectors to ensure that they cannot be closed unintentionally.
  2. Lock or block cutting devices: Secure devices to prevent accidental operation.
  3. Recognize the absence of tension: Verify that there is no electrical current present.
  4. Ground all possible sources of tension: Connect all potential sources of electricity to the ground to prevent shocks.
  5. Place safety signs: Clearly mark the working area to alert others to potential hazards.

3. Causes of Unexpected Tension in an Installation Without Tension

An electrical installation without tension could become energized due to:

  • Falling conductors
  • Atmospheric phenomena (e.g., lightning strikes)
  • Induction
  • Voltage return

Case Study: Tension of Return

Voltage return occurs when there is a breakdown on the main supply line (line 1) and its switch does not open, but the switch for the reserve supply line (line 2) closes.

5. Blocking of a Cutting Device and Application Methods

Blocking a cutting device involves preventing it from operating and keeping it in a specific position. This safeguards against unforeseen events, human error, or technical failures.

Methods of Blocking:

  • Physical block: An insulating element is placed between the cutting parts of the apparatus to prevent contact.
  • Mechanical lock: A lock, padlock, or pin immobilizes the cutting apparatus’s command.
  • Electric lock: Removing the fuse from a general protection device opens the circuit and prevents the cutting device from operating.
  • Pneumatic freeze: Emptying the compressed air power circuit cauldron prevents the switch command from activating.

6. Checking for Absence of Tension in the Work Area

To ensure the absence of tension in the work area of an electrical installation:

  • Use tension absence detectors on all conductors. These devices emit light, sound, or mixed signals to indicate the presence or absence of electrical current.
  • Verify the functionality of the detectors before and after use.
  • Understand that detectors consist of two parts: the detector itself and an insulator beam.

7. Recognizing Absence of Tension in an Airline

A spear gun cable device is used to launch a fuse wire, which is then placed on the conductors of the airline. If the line has tension, the wire melts due to a short circuit, indicating the presence of electrical current.

8. Demarcated Areas in an Electrical Installation

  • Protected area: The section of the installation between the equipment placed at the grounding points located at the line opening.
  • Work area: The space between the closest grounding equipment and the area where work is being done, representing the maximum security zone.

9. Signaling the Work Area

The work area should be clearly defined using tape, signs, and fences to prevent electrical accidents. This transforms the working area into a safe space.

10. IP and IK Codes

These codes represent degrees of protection for electrical equipment:

IP Code

The IP code consists of two numbers and an optional letter:

  • 1st digit: Protection of individuals against access to dangerous parts.
  • 2nd digit: Protection of equipment against the effects of water penetration.
  • Letter (optional): Accessibility of objects or body parts to dangerous parts inside the enclosure.

IK Code

The IK code indicates the degree of protection against mechanical impacts, ranging from 0 to 10. Higher numbers represent greater impact energy resistance.

11. Requirements for Worksite Electrical Installation Components

  • Counters: Designed for a power of 15 kW.
  • Aggression: Made of woven low voltage network.
  • Drivers: Insulated for 1000 V and at a minimum height of 2.5 m from the ground.
  • General protection box: IP 55 degree of protection.
  • General table: Outdoor type, interim assembly, IP 55 degree of protection, and containing all necessary protections.
  • Side tables: Outdoor type, provisional assembly, IP 55 degree of protection (or IP 54 if installed in dry conditions).