Transformer running hot
Overload, blocked ventilation, harmonics or a failing winding. Load measurement and thermal imaging identify the cause.
ELEC-05Electrical
Commercial & Industrial Transformer Service, Testing & Replacement
Most commercial and industrial buildings in the East Bay run 480/277 V distribution with dry-type transformers stepping down to 208/120 V for receptacles, lighting and small equipment. These transformers run for decades with little attention, and when one fails it takes down everything it feeds. We install, test, maintain and replace dry-type transformers and coordinate pad-mounted transformer work with the utility.
- Sector
- Commercial · Industrial
- Coverage
- East Bay, CA
- Scope
- Repair · PM · Install
- Residential
- Not offered
We also address the problems that shorten transformer life: overloading, poor ventilation, harmonic loads from VFDs and electronics, and loose connections at the terminals.
Scope of work
Transformers: what we handle
Equipment
01- General-purpose dry-type transformers, 15 kVA to 1,000 kVA
- K-rated and harmonic mitigating transformers for electronic loads
- Isolation and control transformers for equipment
- Buck-boost transformers for voltage correction
- Energy-efficient replacement transformers meeting current DOE standards
- Pad-mounted utility transformers (coordination and secondary work)
Repair & troubleshooting
02- Overheating and ventilation problems
- Loose or corroded primary and secondary connections
- Failed windings and insulation breakdown
- Noise and vibration from loose cores or mounting
- Tap changes to correct secondary voltage
- Grounding and bonding corrections at separately derived systems
Maintenance
03- Infrared scanning of terminations under load
- Load measurement to identify overloaded transformers
- Cleaning of cores, coils and ventilation openings
- Torque verification of connections
- Insulation resistance testing on older units
Installation & replacement
04- Transformer replacements with minimal downtime planning
- New transformers for equipment additions and tenant improvements
- Upgrades to K-rated units where harmonic loads exist
- Relocation for access, ventilation or space reconfiguration
Diagnostics
Common failures and what they mean
Low voltage on 120 V circuits
Tap settings, overloaded transformer or voltage drop. Correcting tap settings is often a simple fix.
Humming or buzzing that has gotten louder
Loose laminations, mounting hardware or harmonic loading. Worth investigating before it becomes a failure.
Frequent breaker trips on transformer-fed panels
Sometimes a transformer capacity issue rather than a panel problem.
FAQ
Frequently asked questions
Dispatch
Request transformers
Tell us about the facility and the equipment. Attach a nameplate photo if you have one.
East Bay Coverage
Service areas
Transformers for commercial and industrial facilities in these East Bay cities.
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