Commercial Switchboards & Switchgear

Both are used to distribute and control electrical power, but they are not interchangeable terms.

The equipment selected for a project depends on factors such as:

• System voltage

• Available fault current

• Service size

• Required protection

• Equipment configuration

• Maintenance requirements

• Facility type

• Engineered electrical design

Switchboards are common in many commercial distribution systems.

Switchgear is typically used where the electrical system requires a higher level of distribution, protection, isolation, or equipment configuration.

OTC installs the equipment specified for the application rather than assuming every large electrical system should use the same type of gear.

A typical commercial power-distribution path may include:

Utility / Service → Main Service Equipment → Switchboard or Switchgear → Transformers / Distribution Panels → Branch Panels → Equipment & Building Loads

The exact configuration varies by building.

This means a problem at the main distribution level can affect:

• Entire tenant spaces

• Multiple floors

• HVAC

• Lighting

• Production equipment

• Refrigeration

• Building controls

• Large portions of the property

That is why the condition and reliability of major distribution equipment matters.

Major electrical distribution equipment should be evaluated when conditions include:

• Excessive heat

• Discolored bus

• Evidence of arcing

• Abnormal buzzing

• Loose breakers

• Loose or damaged connections

• Corrosion

• Water intrusion

• Repeated breaker failures

• Missing or damaged hardware

• Physical damage

• Difficult-to-source components

• Obsolete or unsupported equipment

• Repeated unexplained outages

Some of these conditions may be repairable.

Others may indicate that replacement planning should begin.

A failed receptacle affects one location.

A failed branch circuit may affect one area.

A major switchboard or switchgear failure can affect an entire building or a significant portion of the facility.

Depending on the system, a failure can create:

• Extended outage

• Loss of HVAC

• Loss of tenant power

• Production shutdown

• Refrigeration loss

• Business interruption

• Emergency repair conditions

That is why major distribution equipment should not be managed purely on a run-to-failure basis when developing warning signs are already present.

Not every problem requires complete replacement.

OTC first evaluates what has actually failed.

Possible repair conditions may involve:

• Breakers

• Connections

• Hardware

• Individual components

• Terminations

Replacement becomes a stronger consideration when the equipment has:

• Significant bus damage

• Extensive overheating

• Arcing damage

• Major corrosion

• Unsupported components

• Poor parts availability

• Repeated failures

• Insufficient capacity for the facility

The decision should consider both the immediate repair and the long-term ability to maintain the equipment.

Older switchboards and switchgear can remain operational for years.

The problem begins when maintaining them becomes increasingly difficult.

OTC considers:

• Breaker availability

• Replacement-part availability

• Manufacturer support

• Equipment condition

• Repair history

• Criticality of the loads

• Cost of downtime

A component may technically still be repairable while the overall system is becoming increasingly difficult to support.

That is when planned modernization should enter the conversation.

Replacing major electrical distribution equipment is not simply a matter of matching the amperage on the existing nameplate.

These projects may require evaluation of:

• Electrical load

• Service requirements

• Available fault current

• Equipment ratings

• Overcurrent protection

• Feeder sizes

• Transformer requirements

• Grounding and bonding

• Selective coordination where applicable

• Utility requirements

OTC coordinates the construction and installation with the project electrical engineer and approved electrical design.

Switchboards and switchgear are frequently manufactured specifically for the project.

Depending on the equipment and market conditions, major electrical gear can have substantial lead times.

Highly customized equipment can sometimes take many months—and certain projects may encounter lead times approaching or exceeding a year.

This makes early planning extremely important.

The process may include:

1. Engineering

2. Equipment specification

3. Manufacturer quotation

4. Submittal review

5. Approval

6. Equipment release

7. Manufacturing

8. Delivery

9. Installation

10. Testing and energization

Waiting until the existing equipment fails can turn a planned capital project into a much more difficult emergency.

Major electrical distribution equipment is not an area where the lowest-cost unknown source should automatically win.

OTC considers factors such as:

• Manufacturer

• Equipment rating

• Product support

• Replacement-part availability

• Warranty

• Lead time

• Compatibility with the engineered design

The equipment may remain in service for decades.

Its long-term supportability matters.

Major commercial service upgrades frequently require new service entrance and distribution equipment.

Depending on the engineered design, that may include:

• Service entrance switchgear

• Switchboards

• Main disconnects

• Metering sections

• Distribution sections

• Main breakers

• Transformers

• Feeder distribution

The new gear becomes part of a larger electrical-service project rather than an isolated equipment replacement.

A switchboard or switchgear project may be driven by expansion rather than failure.

Common triggers include:

• New manufacturing equipment

• Restaurant conversion

• Large HVAC additions

• Warehouse expansion

• New tenant loads

• Building additions

• Increased service capacity

OTC works from the load requirements and engineered design to determine how the upgraded distribution should support both current and reasonable future demand.

The equipment is only one part of the project.

A major distribution upgrade may also require:

• New feeders

• Large conduit systems

• Busway

• Transformer feeds

• Distribution-panel feeders

• Equipment feeders

• Grounding and bonding

• Underground conduit

Changes at the main distribution level can affect a large portion of the electrical system downstream.

Large service and distribution projects may require substantial underground electrical infrastructure.

Depending on the project, that can include:

• Utility conduits

• Service conduits

• Large feeder pathways

• Transformer infrastructure

• Pull boxes

• Equipment pads

• Multiple parallel conduit runs

These pathways should be coordinated early because changing the routing after concrete, paving, or site improvements are complete can become extremely expensive.

Large feeders require more planning than simply determining conductor size.

OTC considers:

• Conduit routing

• Pull lengths

• Number of bends

• Equipment location

• Structural conditions

• Underground opportunities

• Access for installation

• Future serviceability

On major electrical projects, the difference between a well-planned route and a difficult route can represent significant material and labor cost.

Replacing switchboards or switchgear usually requires a major electrical shutdown.

Before the cutover, OTC coordinates:

• Areas affected

• Tenant notification

• Critical equipment

• Refrigeration

• HVAC

• Servers

• Security systems

• Production equipment

• Building controls

• Utility requirements

• Temporary-power needs

The shutdown should be planned before crews begin disconnecting the existing equipment.

On larger replacements, significant work can often be completed before the final shutdown.

The objective is to prepare as much of the new system as practical in advance.

That can include:

• Equipment placement

• Conduit installation

• Feeder preparation

• Grounding

• Downstream coordination

• Labeling

• Testing

Then the final outage can focus on the portions of the work that actually require the existing system to be de-energized.

Some facilities cannot tolerate an extended complete shutdown.

Depending on the property, temporary power or staged electrical work may be considered for selected loads.

Those loads may include:

• Refrigeration

• Critical business equipment

• Servers

• Security

• Production equipment

• Building systems

Temporary power is project-specific and should be planned around what actually must remain operational.

Major electrical distribution equipment should be verified before it is placed into service.

Depending on the engineered requirements, manufacturer instructions, and project specifications, testing may include appropriate:

• Visual inspection

• Mechanical verification

• Connection verification

• Insulation-resistance testing

• Breaker testing

• Functional testing

• Phase and voltage verification

• Control verification

Specialized acceptance testing may be performed by qualified testing agencies when required by the engineer, project specifications, manufacturer, or AHJ.

OTC coordinates the installation and turnover requirements around the specific project.

Large distribution systems may require engineered studies to determine how protective devices should operate together.

Depending on the project, the electrical engineer may address:

• Fault-current calculations

• Protective-device settings

• Selective coordination

• Equipment ratings

• Arc-flash information

OTC installs and sets up the field equipment in accordance with the approved design and project requirements.

Major gear should not disappear from consideration after installation.

Preventive maintenance can help identify developing conditions such as:

• Loose connections

• Excessive heat

• Breaker deterioration

• Corrosion

• Water intrusion

• Abnormal equipment conditions

Finding deterioration during planned maintenance is significantly better than discovering it after the building loses power.

A major switchboard or switchgear project may involve:

• Existing-condition evaluation

• Load and capacity review

• Electrical engineering

• Utility coordination

• Equipment selection

• Submittals

• Long-lead procurement

• Shutdown planning

• Temporary-power planning

• Underground and feeder work

• Equipment installation

• Cutover

• Testing

• Labeling

• Final energization

OTC manages the electrical construction side of that process so the equipment, feeders, and downstream distribution come together as one complete system.