You're right, the world of Surge Protective Devices (SPDs) can be overwhelming. Let's break down the common types used for meter centers in multi-family residential buildings, focusing on practical choices and common applications.

Key Considerations for Choosing SPDs



Location

The closer the SPD is to the equipment you want to protect, the better.

Surge Current Capacity (kA)

Higher kA ratings mean the SPD can handle larger surges and potentially last longer.

Voltage Protection Rating (VPR) / Suppressed Voltage Rating (SVR)

A lower VPR/SVR indicates better protection. This is the maximum voltage the SPD will allow to pass through to the protected equipment during a surge.

Mode of Protection

Common modes include Line-Neutral (L-N), Line-Ground (L-G), and Neutral-Ground (N-G). Look for SPDs that offer protection for all modes.

UL Listing

Ensure the SPD is UL Listed (or equivalent certification) to meet safety standards and code requirements. Specifically, UL 1449 is the standard for SPDs.

Ease of Installation

Consider how easy it is to install the SPD within the meter center enclosure.

Monitoring & Indication

Look for SPDs with visual or audible indicators to show when the SPD is functioning correctly. Some have remote monitoring capabilities.

Compliance

Be sure to be compliant with all current and local regulations, like NEC or local ordinances

Common SPD Types for Multi-Family Meter Centers

The typical approach is a layered protection strategy. This means having surge protection at multiple points in the electrical system. For a meter center in a multi-family building, you'll commonly see:1.

Type 1 or Type 2 SPD at the Main Service Entrance

This is the first line of defense.

Type 1 SPDs

These are designed to be installed before the main overcurrent protective device (OCPD) and can withstand higher surge currents. They are often used where the risk of very large surges (like direct lightning strikes) is higher. Because they are installed upstream of the main breaker, they are typically more robust.

Type 2 SPDs

These are designed to be installed after the main overcurrent protective device. They are more common and often more cost-effective than Type 1 SPDs.

Specifications



kA Rating

Typically 80kA to 200kA, or higher, depending on the building's risk assessment.

Voltage

Appropriate for the service voltage (e.g., 120/240V single-phase, 120/208V or 277/480V three-phase).

Mounting

Often DIN rail mountable within the meter center enclosure, or NEMA-rated enclosures for external mounting.

Monitoring

LED indicators are common, and some have dry contacts for remote monitoring.2.

Type 2 SPDs at Sub-Panels (Optional but Recommended)

Adding SPDs at sub-panels within individual apartments/units provides an additional layer of protection for sensitive electronics.

Specifications



kA Rating

40kA to 80kA is usually sufficient.

Voltage

Appropriate for the panel voltage (typically 120/240V).

Mounting

Often designed to be installed inside the panel, or adjacent to it.3.

Type 3 SPDs at Point of Use (Optional)

These are plug-in surge protectors (power strips with surge protection) used at outlets to protect individual devices.

Specifications



kA Rating

Lower kA rating (e.g., a few kA to 10kA). These are intended for smaller, localized surges.

Voltage

120V

Considerations

While these offer some protection, they should not be relied upon as the primary surge protection. They are more of a supplemental layer.

Common SPD Brands and Models



Eaton

Offers a wide range of SPDs for various applications.

Siemens

Another reputable manufacturer with comprehensive surge protection solutions.

Schneider Electric (Square D)

Well-known for their electrical equipment, including SPDs.

Leviton

Provides a variety of SPDs, including those suitable for residential applications.

ABB

A global leader in power and automation technologies, offering a range of SPDs.

Example Specifications



For the Main Service Entrance (Type 1 or 2)

Voltage: 120/240V Single Phase, 3W+G Surge Capacity: 100kA minimum (consider higher for areas with frequent lightning) SCCR: 200kA NEMA 4 Enclosure: for exterior mounting.

Important Considerations for Multi-Family Buildings



Coordination with the Utility Company

Check with the local utility company for any specific requirements or recommendations regarding surge protection at the service entrance.

NEC Compliance

Ensure that the SPD installation complies with the latest edition of the National Electrical Code (NEC). Article 230 and Article 285 are particularly relevant.

Grounding

Proper grounding is critical for the effectiveness of SPDs. Ensure that the grounding system is adequate and meets code requirements.

Future Expansion

Consider the possibility of future expansion when selecting the SPD. Choose a model with sufficient capacity or the ability to add modules later.

Budget

Balance the level of protection with the budget. While it's tempting to go with the cheapest option, investing in a good quality SPD can save money in the long run by protecting valuable equipment.

Whole House Surge Protection vs. Point of Use Surge Protection In many cases, a whole house surge protector is more cost effective than putting surge protectors on every outlet.

Steps to Take


Determine the Service Voltage and Configuration

(e.g., 120/240V single-phase, 120/208V three-phase).2.

Assess the Risk

Is the building in an area with frequent lightning strikes? What is the value of the equipment being protected?3.

Check Local Codes and Utility Requirements

Are there any specific requirements for surge protection in your area?4.

Consult with an Electrical Engineer or Qualified Electrician

They can help you select the appropriate SPD based on your specific needs and ensure proper installation.5.

Create a Surge Protection Plan

A layered approach, starting at the service entrance and extending to sub-panels and point-of-use devices, is generally the most effective.

In summary:

For meter centers in multi-family residential buildings, a Type 1 or 2 SPD at the main service entrance is essential. Adding Type 2 SPDs at sub-panels* is highly recommended for enhanced protection.It is always best to consult with a qualified electrician or electrical engineer to determine the specific needs of your building and ensure that the SPD is properly installed and meets all applicable codes and regulations. They can also help you to compare the different brands and models available and choose the one that best fits your budget and requirements. Flag for review