Okay, I've reviewed the image you provided and considered the scenario you described. Here's a breakdown of the situation, potential code implications, and things to consider

Understanding the Configuration
Combo Panel

This is a combination load center and meter socket, typically found in residential services.

Main Disconnect

The main breaker disconnects all power downstream of it in the panel.

Sub-Panel Breaker (Before Main)

This is the key issue. You have a breaker that feeds a sub-panel located upstream of the main disconnect. This means it remains energized even when the main breaker is switched off.

Legality and Code Considerations

While it's impossible to make a definitive legal judgment without a full on-site inspection and knowledge of the specific local codes enforced at the time of installation (2002-2003), here's a discussion of relevant considerations: NEC (National Electrical Code)

The NEC is updated every three years, so the specific edition in force in your area in 2002-2003 would be crucial. I cannot say for certain which edition was enforced at the time of installation. However, the NEC generally focuses on safety and accessibility. A configuration like this could potentially violate a few aspects:

Accessibility of Disconnect

The NEC requires that all electrical circuits be able to be shut down for servicing, repair, and upgrades. Having a circuit energized even when the main disconnect is off creates a hazard for anyone working on the "de-energized" panel.

Overcurrent Protection

The branch circuit feeding the sub-panel must be properly protected.

Clear Labeling

The panel MUST have clear labeling indicating that a circuit remains energized even when the main breaker is off. This is critical for safety.

Local Amendments

Many jurisdictions amend the NEC. Local codes may have been more or less strict than the NEC.

Why It's Unusual and Potentially Problematic Safety Hazard

As mentioned above, this setup creates a significant safety hazard for anyone working on the electrical panel, assuming the main disconnect has killed the power.

Unexpected Energized Circuit

It can be confusing and unexpected. Most people assume that when the main breaker is off, the entire panel is de-energized.

Limited Functionality

The purpose of the main disconnect is to isolate the entire load center. This configuration defeats that purpose, as there is still a source of power within the enclosure.

Work on the Meter

When the main disconnect is off. The homeowner believes it's safe to work downstream of the main. However, that subpanel breaker upstream of the main is energized and could be feeding a circuit inside the house.

Unmetered Power Potential

While unlikely in a residential setting, some have concerns about unmetered power being pulled upstream of the meter.

What To Do1. Contact a Qualified Electrician

This is the MOST important step. A licensed electrician can: Inspect the entire installation and verify that it meets code requirements for 2002-2003 (or current code if modifications are made). Identify any potential safety hazards. Determine if the configuration is acceptable under local codes. Provide options for correcting any issues, such as moving the sub-panel feed to a location downstream of the main disconnect.2.

Check with Your Local Building Department

They can provide information on the specific codes enforced in your area at the time the house was built.

Possible Explanations for the Configuration (But Don't Assume - Get an Inspection!) Specific Load Requirements

Sometimes, in very specific situations, there might have been a need for a continuous, unswitched power supply for essential equipment (like fire alarm systems or critical life-support equipment). However, even in those cases, strict code compliance and labeling are vital. This is unlikely in a typical residential setting.



Mistake/Non-Standard Practice

The most likely reason is that the installation was simply not done according to best practices or was a misinterpretation of the code.

In summary, while it's possible that this configuration met code requirements at the time of installation, it's highly unusual, presents potential safety hazards, and should be thoroughly inspected by a qualified electrician.* Don't rely on online opinions – get a professional assessment! Flag for review