Run Transformer Pre-Energization Checklist — Free

Inspection Details and Safety Controls

Transformer identification matches the approved commissioning record critical (required)

Verify nameplate data, serial number, kVA/MVA rating, voltage class, and location match the energization package.

Yes No N/A

Photo evidence (optional)

Lockout-tagout and switching order are in place critical (required)

Confirm the transformer and associated circuits are controlled under an approved lockout-tagout procedure per OSHA 1910.147.

Yes No N/A

Required PPE is selected for the task critical (required)

Select the PPE required by the energized work boundary and hazard assessment per NFPA 70E.

Work area is barricaded and access is controlled critical (required)

Verify the area is clear of unauthorized personnel and barriers/signage are installed as required.

Yes No N/A

Inspection package and approved drawings are available

Confirm the latest one-line, settings sheet, test results, and energization authorization are available to the inspector.

Yes No N/A

Transformer Condition and Oil System

Oil level is within the acceptable operating range critical (required)

Verify the oil level indicator is within the manufacturer-specified normal range and no low-oil alarm condition is present.

Yes No N/A

Photo evidence (optional)

No visible oil leaks, seepage, or active drips critical (required)

Inspect the tank, valves, gaskets, radiators, conservator, and fittings for leakage.

Yes No N/A

Photo evidence (optional)

Pressure relief device, breather, and conservator components are intact critical (required)

Confirm visible condition of pressure relief, silica gel breather, and conservator piping where applicable.

Yes No N/A

Tank, radiators, and fittings are free of physical damage

Check for dents, corrosion, loose hardware, missing covers, or other non-conformances that could affect safe operation.

Yes No N/A

Oil sampling, test, and filtration records are complete

Confirm required oil quality checks, moisture results, and any filtration or degassing actions were completed and accepted.

Yes No N/A

Bushings, Terminations, and Grounding

Bushings are clean, intact, and free of cracks or chips critical (required)

Inspect all high- and low-voltage bushings for contamination, damage, tracking, or oil leakage.

Yes No N/A

Photo evidence (optional)

Bushing connections and hardware are tight and properly torqued critical (required)

Verify terminations, jumpers, and hardware are secure and installed per approved torque specifications.

Yes No N/A

Grounding connections are installed and continuous critical (required)

Confirm tank ground, neutral ground, and any equipment grounding conductors are present, secure, and bonded.

Yes No N/A

Ground resistance or continuity test result is acceptable critical (required)

Record the measured grounding continuity or resistance value used by the commissioning procedure.

Surge arresters and neutral links are correctly installed

Verify arrester connections, neutral links, and any removable bonds are installed per design.

Yes No N/A

Electrical Tests and Tap Configuration

Insulation resistance (IR) test completed and acceptable critical (required)

Enter the measured insulation resistance value and confirm it meets the project or manufacturer acceptance criteria.

Turns ratio test (TTR) results are within tolerance on all required tap positions critical (required)

Verify the TTR test was completed and all measured ratios are within the acceptable tolerance for each required tap position.

Yes No N/A

Photo evidence (optional)

Tap changer position matches the approved energization setting critical (required)

Confirm the off-circuit or on-load tap changer is set to the documented pre-energization position.

Winding polarity, phase rotation, and vector group are verified critical (required)

Confirm test results match the design data and system interconnection requirements.

Yes No N/A

Protection, Controls, and Final Readiness

Protection relays and settings match the approved coordination study critical (required)

Verify relay settings, CT/PT ratios, and trip logic correspond to the approved setting sheet.

Yes No N/A

Alarm and trip circuits are functional critical (required)

Confirm any required alarm, trip, and indication circuits have been checked and are operational.

Yes No N/A

All covers, barriers, and access panels are secured critical (required)

Verify all removable covers, doors, and access points are closed and secured prior to energization.

Yes No N/A

Transformer is approved for energization by the responsible authority critical (required)

Final authorization is confirmed by the commissioning lead, competent person, or AHJ as applicable.

Yes No N/A

Inspector Findings and Sign-Off

Deficiencies or non-conformances noted

List any deficiencies, observations, or exceptions identified during the inspection.

Corrective actions completed or assigned

Document corrective actions, responsible party, and target completion date if applicable.

Inspector signature

Signature of the inspector completing the pre-energization checklist.

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Run: Transformer Pre-Energization Checklist

Inspection Details and Safety Controls

Transformer Condition and Oil System

Bushings, Terminations, and Grounding

Electrical Tests and Tap Configuration

Protection, Controls, and Final Readiness

Inspector Findings and Sign-Off

Get your results