Ask for evidence that fits your project
A manufacturer’s headline capacity is only a first filter. The useful question is whether the proposed design, documentation and supply scope match your installation. Start with a written technical brief, then compare how each bidder responds to it. A generic brochure, a photograph or a company certificate cannot answer every product-specific question.
For OSTL, the confirmed company facts include manufacturing since 2007, a transformer unit in Howrah, a Kolkata corporate office, and in-house radiator manufacturing at Sankrail, Howrah, from 2026. These facts provide context; your procurement decision should still examine the particular offer.
Use a document-led review
| Review area | What to ask for |
|---|---|
| Product fit | Written confirmation of rating, voltage, type, winding material, installation conditions and any exclusions. |
| Licensing and standards | Current documents and exact category/scope applicability for the proposed product, not a general logo alone. |
| Technical proposal | A completed technical schedule, drawing status, interfaces, agreed performance figures and deviations. |
| Testing and inspection | The proposed routine-test schedule, documentation, witness arrangements and any separately agreed type or special tests. |
| Commercial scope | Packing, freight, unloading, installation responsibilities, requested timeline, warranty terms and payment terms. |
| Traceability | A clear connection between the quoted design, approved documents, nameplate details and delivered-unit test records. |
Separate company credentials from product approval
OSTL is ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 certified, and BIS licensed in five major transformer categories. Copies available on request; ask for the documents and the product scope that apply to your purchase. A management-system certificate is not a substitute for checking the transformer specification, and a BIS statement should not be extended to an unverified rating or design.
Similarly, a project or utility approval must be checked for its exact relevance and validity. Do not infer an approval, export eligibility or a customer reference from a market page or a general manufacturing claim.
Make quotation differences visible
- Ask each bidder to identify technical deviations, not just provide a general compliance statement.
- Compare offers on the same loss/performance basis and the same included accessories and documentation.
- Treat an unusually short delivery promise or low price as a question to clarify, not evidence of quality or poor quality by itself.
- Agree which information must be approved before manufacture, inspection and dispatch.
- Keep the final technical and commercial agreement in writing.
Discuss the facilities and the process
Use the existing facilities overview to understand OSTL’s Kolkata and Howrah footprint. The manufacturing-process animation is a conceptual explanation, not evidence of a particular factory test facility or a guaranteed construction method. Discuss the actual product and any requested inspection directly with the Kolkata office.
Prepare the comparison
Prepare a useful quotation brief
A practical technical and commercial checklist, plus a copyable/downloadable template.
↗GENERAL TECHNICAL GUIDANCEUnderstanding routine tests
Learn what to ask about test scope and reports without assuming an unverified facility capability.
↗EXISTING REGIONAL PAGESFind the relevant region
Use the existing location guidance; no duplicate city/rating pages are needed.
↗