- Electrical Safety Tutorial
- Electrical Safety - Home
- Power System
- Indian Standards
- Low Voltage Overload Protection
- Short Circuit Protection
- Earth Fault Protection
- Earthing
- Types of the Supply System
- Cables
- Classification of Hazard-Prone Areas
- Safety Measures Related to Gas/Ducts/Fibre material
- Classification of Temperature
- Protection Against Weather Complexities
- Safe Electrical Equipment Design Characteristics
- Test Certifications
- Procedure to Mark Unprotected Equipment
- Maintenance of Unprotected Equipment
- Duties and Obligations
- Primary Ex-protection
- Secondary Ex-Protection
- Precautions Against Highly Flammable Contents
- Safety Measures During Handling Lighting Protection Equipment
- Bonding
- Transformer Safety
- Motor Handling Safety
- Generator Handling Safety
- Crane Handling Safety
- Safety Measures During Preventive Maintenance
- Types of Safety Equipment
- Implications of Human Behaviour
- Do's and Don'ts at a Glance
- Electrical Safety Useful Resources
- Electrical Safety - Quick Guide
- Electrical Safety - Useful Resources
- Electrical Safety - Discussion
Protection Against Weather Complexities
It has now become common that with bad weather like storm or heavy rains, there will be loss of power or electricity. This affects the masses at large. And, people at the coastal regions are the most affected when there is failure of electricity due to flooding. 67% of the electrical outage instances have been a result of natural calamities such as lightening, snowfall and wind. To minimize the cost and mitigate issues of outage, protecting electrical assets is necessary.
Protecting Electrical Network
In this section, we will see how to protect electrical networks from natural calamities.
Maintenance
For critical systems, UPS and the backup generator should be installed and maintained properly. If the power is cut off from the grid, the backups are utilized. Regular maintenance service ensures the reliability of equipment and safer work environment.
Electrical Network Design
Correct electrical design minimizes the voltage transients generated when there is lightening. An electrical model should be tested through all possible scenario; the faults and weaknesses of various areas are to be predicted. A proper design should provide −
- redundancy
- alternative paths
- automatic transferring loads
Testing of System
The backup supplies and alternative paths should be tested periodically. Consider testing the following −
the condition of backup equipment
the system logic in case of failure or for new installations
the response of site personnel in emergency situation when the utility supply fails
Management
Data management and analytics help in predicting the problems, finding solution to prevent the problems or solve an already occurred problem. The management system focuses on the following two areas −
Outage Management System
The OMS provides data and information from a variety of sources, faults, allowing maintenance and engaging electrical workers to repair and restore.
Asset Management System
A track record of facility’s assets, predicted lifecycle and technical specifications must be maintained to ensure a reliable and resilient network.
Protection against extreme weather condition
The extreme weather condition refers to the lightning that could be catastrophic for the electric devices. Consider the following points to keep your devices safe.
An electrical surge can fry a circuit board of electronic equipment like TV, laptop and sound system, etc. A top-notch surge protector can be used to prevent the damages.
There are three characteristic that need to be considered while buying a high-quality surge protector (SP) −
Low clamp level − It takes a voltage to trigger the SP and to divert the electricity to the ground
Low response time − It takes nanoseconds of time to respond the surge
High surge capability − It takes some amount of voltage that an SP can take and function properly
It is not required to depend upon the warranty of SP. Attach a status check light with it which shows the last surge.
Avoid overloading a power strip surge protector, which may increase the risk of damaging the electronic equipment.
Standards against Dirt and Water
According to the International Electro-technical Commission (IEC) standards 60529, the International Protection Marking classifies the degree of protection which is provided against intrusion, dust, accidental contact and water by the mechanical casing and electrical enclosure. The Ingress Protection (IP) defines from which the equipment is protected in normal condition. The first digit indicates the protection of equipment against solids. The second digit indicates the protection of equipment against harmful entry of various forms of moisture.
The following table lists down the IP Codes and their meanings −
| 1st digit | Protection from Solid | 2nd digit | Protection from Moisture |
|---|---|---|---|
| 1 | Hand Protected: protection from solid objects greater than 50mm in diameter | 1 | Drip proof against vertical water drops |
| 2 | Finger protected: protection against the object > 12.5mm | 2 | Drip proof when tilted at angles up to 15ᵒ |
| 3 | Tool protected: protection from the object with a diameter or thickness > 2.5mm | 3 | Rain/Spray proof when water falling at an angle up to 60ᵒ |
| 4 | Wire protected: protection against the objects with a diameter or thickness > 1.0mm | 4 | Splash-proof when water splashed from any direction |
| 5 | Dust accumulation protected: protection from the dust interfering with the operation | 5 | Jet proof when water projected through a nozzle(dia 6.3 mm) at a pressure from any direction |
| 6 | Dust penetration protected: protection against penetration of dust | 6 | Jet proof when water projected through a nozzle(dia 12.5 mm) at a pressure from any direction |
| 7 | Watertight proof when temporary immersion in water | ||
| 8 | Pressure watertight when continuous submersion in water |
The following table lists down the letters that define hazardous parts. Some other letters provide additional information related to the protection of the equipment.
| Level | Hazardous parts |
|---|---|
| A | Back of hand |
| B | Finger |
| C | Tool |
| D | Wire |
The following table lists down a few letters in IP codes −
| Letter | Meaning |
|---|---|
| F | Oil resistant |
| H | High voltage device |
| M | Device moving during water test |
| S | Device standing still during water test |
| W | Weather conditions |
Questions
1. Which device requires nanoseconds of time to respond the surge?
a) Low clamp level device
b) Low response time device
c) High surge capability device
d) None of these
Ans: b
Explanation
Justifying the name, the low response time device requires only nanoseconds of time to respond to the surge, recognize the fault and commands the protective device to trip.
2. IP codes follow the standard of __________.
a) IEC
b) BIS
c) NFPA
d) NEMA
Ans: a
Explanation
The International Electro-technical Commission of Europe describes the Ingress Protection of mechanical and electrical enclosures of equipment.
3. What is the meaning of enclosure IP56?
a) Protection against insertion of the finger and vertically dripping in water
b) Dust resistant and can be immersed in water
c) Protection against dust and high-pressure water jets from any direction
d) None of these
Ans: c
Explanation
In IP56, the first digit 5 refers to protection against dust and the second digit 6 refers to the protection from high-pressure water jets from any direction. By combining both digits, the outcome refers to option C.