Checklists by equipment
2 lists · 11 items · 17 photosDry-type transformer maintenance checklists
Dry-type transformer maintenance checklists for the quarterly and annual rounds: 2 free lists, 11 items and 17 photo requirements, each item naming what to look for and the photo that proves it. Work is commonly verified against NFPA 70B and NETA acceptance and maintenance testing; the edition in force is the AHJ's call on each project.
The dry-type transformer rounds
Dry-type transformer QuarterlyDry-type transformer quarterly maintenance checklistAirflow, hum, enclosure heat and clearances checked energized without opening the transformer6 items8 photosDry-type transformer AnnualDry-type transformer annual maintenance checklistDe-energized torque, cleaning and coil inspection done during the outage alongside the NETA testing tech5 items9 photos
Where each walk sits in the schedule
- Dry-type transformer quarterly maintenance checklistquarterly
- Every quarter, scheduled for a loaded part of the day so the reading reflects real heat, not an idling unit. Run by: The facility electrician on the quarterly electrical round, working entirely outside the enclosure with the unit energized.
- Dry-type transformer annual maintenance checklistannual
- Once a year during a scheduled shutdown, coordinated with the NETA technician so the transformer is locked out, cleaned and torqued while it's cold, then tested before it's re-energized. Run by: The facility electrician recording the inspection during a planned outage, working the connections while the testing firm performs the electrical tests on the same unit.
What most often fails on a dry-type transformer
- Louvers half-blocked by pallets or boxes stacked against the enclosure in a tight electrical room, so the winding runs hot all summer.
- A rising hum or buzz noted by the operator but never logged, so a loosening core clamp is only found after it rattles loose.
- Termination heat never scanned because the covers stay on, so a warm lug isn't caught until it discolors.
- Coils blown out with compressed air that just packs conductive dust deeper into the winding slots instead of vacuuming it out.
- Bolted connections re-tightened by feel with no torque wrench, so half are over-crushed and half never reached spec.
- The unit closed up and returned to service before the testing tech's insulation-resistance readings are back and recorded.
Verified against
Families only, never clause numbers. Adoption varies by jurisdiction; confirm the edition your authority having jurisdiction enforces before you run a walk against it.
Common questions
- Which dry-type transformer maintenance rounds do these checklists cover?
- Dry-type transformer quarterly maintenance checklist (quarterly): Every quarter, scheduled for a loaded part of the day so the reading reflects real heat, not an idling unit. Dry-type transformer annual maintenance checklist (annual): Once a year during a scheduled shutdown, coordinated with the NETA technician so the transformer is locked out, cleaned and torqued while it's cold, then tested before it's re-energized.
- Who runs the dry-type transformer maintenance round?
- The facility electrician on the quarterly electrical round, working entirely outside the enclosure with the unit energized. The facility electrician recording the inspection during a planned outage, working the connections while the testing firm performs the electrical tests on the same unit.
- What most often fails on a dry-type transformer?
- Louvers half-blocked by pallets or boxes stacked against the enclosure in a tight electrical room, so the winding runs hot all summer. A rising hum or buzz noted by the operator but never logged, so a loosening core clamp is only found after it rattles loose. Termination heat never scanned because the covers stay on, so a warm lug isn't caught until it discolors. Coils blown out with compressed air that just packs conductive dust deeper into the winding slots instead of vacuuming it out.
- Which standards is dry-type transformer work verified against?
- NFPA 70B, published by the National Fire Protection Association; NETA acceptance and maintenance testing, published by the InterNational Electrical Testing Association. Adoption varies by jurisdiction. Confirm the edition your authority having jurisdiction enforces before you run a walk against it.
- Can I run these checklists in RTI?
- Yes. Start a free RTI workspace and load any of the 2 lists (11 items in total). The Photo Gate holds the submit button until every mandatory item is answered and its photos are attached, and approved inspections roll into a branded turnover package with a tamper-evident audit trail.