Commercial · Franklin County & St. Louis, MO

    Commercial Electrical Service Upgrades in Franklin County & St. Louis, MO | CAS Electric

    New equipment, an addition, or a new tenant pushing you past your current electrical service capacity? CAS Electric handles commercial service upgrades — single-phase and 3-phase — across Franklin County and the Greater St. Louis area — Pacific, Washington, Union, Sullivan, St. Clair, Eureka, Wildwood, Villa Ridge, and Marthasville, with Ameren coordination and permit handling included.

    About Commercial Service Upgrades

    Commercial service upgrades happen for one of a few reasons: new equipment (HVAC, ovens, compressors, CNC) has pushed calculated load past service capacity; a tenant improvement is adding load the shell wasn't sized for; a growing business needs 3-phase where they used to have single-phase; or an aging service is at its useful-life limit and needs replacement.

    We handle all of it. That includes coordinating with Ameren Missouri on service size, meter type, and CT metering if the service crosses the threshold; specifying and installing the switchgear, distribution panel, and any sub-panels; and running the mains from the utility termination to the distribution panel.

    Because commercial service upgrades affect building operations, we plan the cutover carefully — often after hours or on a weekend — and coordinate with tenants, IT, refrigeration, and any other systems that can't tolerate an outage. You'll have a clear cutover plan with defined windows before the day arrives.

    Why Choose Commercial Service from CAS Electric

    Single-phase and 3-phase service upgrades
    Ameren coordination on service size, meter, and CT metering
    After-hours or weekend cutovers to minimize downtime
    New distribution and sub-panels sized for future growth
    Full permit and inspection handling
    Coordination with IT, refrigeration, and other critical systems

    Our Process

    Commercial service upgrades are quoted per project based on service size, phase, switchgear, and distribution scope. Costs vary widely depending on scope — we provide a free written estimate after a site visit.

    1. 1

      Load calculation & Ameren scoping

      We calculate your existing plus planned load and scope the correct service size with Ameren.

    2. 2

      Written scope, price, and cutover plan

      You get a clear price and a written cutover plan showing exactly when power is off and for how long.

    3. 3

      Cutover install

      Switchgear, distribution, mains, and any sub-panels installed — often after hours or on a weekend to minimize disruption.

    4. 4

      Inspection & Ameren re-energize

      Inspector signs off, Ameren re-energizes, and we walk you through the new distribution and labeling.

    Why Choose CAS Electric

    • Commercial single-phase and 3-phase service upgrade experience
    • Ameren coordination handled — you don't chase the utility
    • After-hours cutovers to protect your operations
    • Detailed cutover planning with defined outage windows
    • As-built panel schedules and labeling handed off at completion

    Frequently Asked Questions

    How long is my business without power?+

    Depends on scope, but most commercial cutovers are planned for 4–10 hours during off-hours (nights, weekends) so operations aren't affected. We build the cutover plan around your operating schedule.

    Do you handle 3-phase service upgrades?+

    Yes — single-phase and 3-phase, including CT-metered services for larger buildings. We coordinate directly with Ameren on service size, phase, and metering type.

    Can you upsize incrementally as we grow?+

    In most cases we spec the service with 25% growth headroom above your current calculated load. Going bigger is cheaper now than upgrading again in 3 years.

    Do we need city approval on top of Ameren?+

    Yes — the local building department pulls the electrical permit and inspects. We coordinate both approvals as part of the project.

    Can you work with our existing distribution or do we replace it?+

    Depends on age and condition. Sometimes the existing distribution panel is fine and we're just upsizing the incoming service; sometimes it makes sense to replace the switchgear at the same time. We'll give you an honest recommendation.

    Get a Free Commercial Service Estimate

    Licensed, insured, owner-operated. We respond to all estimates within 1 business day.