Transformer procurement scenario

“OLTC Included” Still Left Five Transformer Decisions Unmade

Send the required tap range, number of positions, control voltage and remote indication requirements for review.

“OLTC Included” Still Left Five Transformer Decisions Unmade educational procurement flow diagram

The moment the missing scope appeared

Lucía read “OLTC included” in the offer and assumed the difficult voltage-regulation question had been closed. During drawing review, five unanswered decisions appeared: regulation range, number of positions, control voltage, local/remote operation, and position feedback. The oil compartment and maintenance provisions were not even listed.

Why the shortcut was dangerous

An OLTC is a system, not a checkbox. Its drive, limits, interlocks, indication, oil service, operation counter and tests must match the voltage-control requirement. A supplier can honestly include an OLTC and still quote a configuration that differs from the project intent.

What the engineering evidence says

DETC requires isolation and de-energization. OLTC operates in service. That single boundary changes equipment complexity and operating responsibility. The buyer needs a parameter table, control diagram, signal schedule and maintenance scope—not only the three letters OLTC.

How TransformerGrid structures the review

TransformerGrid aligns all bidders on the same tap-changer matrix and checks that the nameplate, drawing, control diagram and FAT record describe the same positions and functions.

Information to send before quotation

  • Tap range and step
  • Number of positions and rated tap
  • Control voltage and modes
  • Position indication and protocol
  • Oil, filtration, maintenance and spares

Explore the complete accessories cluster

Selected through documented State Grid tenders. Proven across demanding climates.

Our verified manufacturing partner holds documented State Grid tender awards for projects in Heilongjiang and Fujian—covering severe cold and hot, humid coastal service.

No failures are recorded for the documented installed units during the verified operating period.

Send the required tap range, number of positions, control voltage and remote indication requirements for review.

TransformerGrid coordinates technical review, verified manufacturing, FAT and international delivery. Manufacturing and operating evidence is attributed to the verified manufacturing partner and the documented project scope.