Protection against the Surges

An Indian & Southeast Asian Perspective.

PART 1: The Point of Use Approach.

The importance of surge protection can never be overstated. It is vital to protect your equipment against voltage surges and transient overvoltages. The longevity of the installed equipment and the reliability of the overall electrical installation depends upon it. In the Indian and Southeast Asian context, the direct lightning strikes may not be a significant concern rather the TOVs due to inductively coupled surges are a much bigger concern. It is important that the conventional approach of surge protection installations that is from Type 1 -> Type 3 needs to be critically thought about before installation in these and similar regions.

In Indian and Southeast Asian regions, the prevailing issue of surge protection is less likely due to direct lightning strikes rather than inductively coupled surges. These surges occur when there is a sudden change in the electrical current in the electrical vicinity, often caused by factors like load shedding, power switching or grid instability. These inductively coupled surges are as damaging as direct lightning surges, if not more to your electrical equipment.

The aspects and the impact of inductive coupled surges could be as complicated as the human brain can think, but it can be expressed as simply as illustrated under.

A quick recap of the prevailing types of surge protection devices:

• Type 1: Installed at the service entrance, these are referred to as the highest level of protection; rather these are coarse levels of surge protection against direct lightning strikes and external surges.
• Type 2: Located at the distribution panels, it protects against downstream from the service entrance.
• Type 3: These are the most localized protection devices, typically installed at the point of use, such as individual appliances or sensitive equipment.

These devices implement different technologies to achieve the desired protection from arc-gap arresters, gas discharge tubes to Zinc Oxide Varistors.

Many individuals and even professionals often adopt the approach of beginning their surge protection efforts with Type 1 devices. Not to undermine their reasoning of ‘first line of defence’ should be more robust but this approach has several drawbacks, especially from the Indian and Southeast Asian perspectives.

Placing Type 1 devices first at the entrance may lead to overprotection, especially in zones that do not have frequent direct lightning strikes. Overprotection can result in unnecessary expenses & maintenance. It is very often seen that the service owners in developing countries work on limited budgets for such protection and often tend to compromise on further stages of protection thinking that their installation is adequately protected.

The Rational Approach: The Point of Use approach.

Given the prevalence and impact of inductively coupled surges in India and Southeast Asia, it makes more sense to adopt the following installation sequence:

• Stage 1: Start by installing Type 3 SPDs at the point of use, protecting individual appliances and sensitive equipment. This localized protection is vital to mitigate inductively coupled surges.
• Stage 2: Next, move on to Type 2 SPDs at distribution panels. These provide additional protection against surges that may enter the system from external sources.
• Stage 3: Install Type 1 SPDs at the service entrance. While direct lightning strikes may be less common, these SPDs act as the last line of defence against the rare occurrence of high-energy surges due to load shedding or in the event of grid instability.

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Advantages of Point of Use Approach:

• Focused Protection: Starting with Type 3 SPDs addresses the primary concern of inductively coupled surges, providing targeted protection where it's needed most.
• Cost Efficient: This approach brings far more value to the service owners by optimizing resource allocation and avoiding unnecessary expenses and high maintenance costs.
• Minimized Downtime: By adopting a ‘point of use’ approach the service owners reduce the risk of downtime caused by inductively coupled surges.

In India and Southeast Asia, where inductively coupled surges pose a significant threat to electrical systems and equipment, it's imperative to rethink the installation order of SPDs. Prioritizing Type 3 SPDs at the point of use and progressively moving to Type 1 SPDs at the service entrance is a strategic approach that aligns surge protection with the region's unique challenges. Remember, in the world of surge protection, it's not just about following the conventional path but adapting to the specific needs of your region for the effective safeguarding of your electrical assets.

Future read: As mentioned, this is Part 1 which narrates the approach. Part 2 will be focused on the technology of Type 3 devices and their monitoring capabilities.

Feel free to write me in the LI message or reach out on my email id [email protected] to brainstorm ideas for probable surge protection schemes.

No protection is absolute but by interaction, we can definitely improve it.