Range & products
What does OSTL manufacture?
OSTL manufactures power and distribution transformers up to 10 MVA and 66 kV, and dry-type transformers up to 3 MVA.
FAQ
Answers before
the enquiry.
Straightforward answers about the range, quality framework and the details needed to start a transformer enquiry.
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START WITH THE ESSENTIALSRating. Voltage. Quantity.
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For project-specific configurations and commercial details, speak with OSTL directly.
Range & products
What recognition has OSTL received?
OSTL was felicitated by SAIL (Steel Authority of India Ltd.) for performance and contribution in 2025, at the IIMM Vendor Meet.
Range & products
Which winding materials are available?
Copper and aluminium windings are available. Confirm the appropriate material and product-specific configuration with OSTL.
Range & products
Is OSTL BIS licensed?
OSTL is BIS licensed in five major transformer categories. BIS licences were acquired in all five categories in 2020.
Range & products
What is the manufacturing range?
Power and distribution transformers: up to 10 MVA and 66 kV. Dry-type transformers: up to 3 MVA. Product-specific configurations and voltages are confirmed against your enquiry.
Range & products
Where are OSTL’s manufacturing facilities?
The transformer manufacturing unit is in Howrah, West Bengal. OSTL expanded into in-house radiator manufacturing in 2026 at Sankrail, Howrah. Total manufacturing area is over 20,000 sq ft. The corporate office is in Kolkata.
Range & products
Do you manufacture dry-type transformers?
Yes. OSTL manufactures dry-type transformers up to 3 MVA. Share the required rating, voltage and installation details to confirm the configuration.
Range & products
What information is needed for a quotation?
Please provide your name, company, phone and email, kVA rating, voltage, quantity, delivery state or country, requested timeline and any additional specifications.
Quality & testing
Which standards are relevant to routine testing?
For power and distribution transformers, routine tests are carried out per IS 1180 / IS 2026 as applicable. Confirm product-specific test requirements with OSTL.
Quality & testing
Which quality credentials does OSTL hold?
OSTL is ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 certified, and BIS licensed (IS 1180) in five major transformer categories. Copies available on request.
Enquiries & contact
How can I confirm a dispatch timeline?
Share your specification, quantity and requested timeline so OSTL can confirm the dispatch schedule for your enquiry.
Enquiries & contact
How can I contact OSTL?
Call or WhatsApp +91 93310 15264, call the office on 033 4061 3200, or email ostltd@hotmail.com.
Enquiries & contact
Where is the office?
Our office is at 33A Jawaharlal Nehru Road, Chatterjee International Centre, 8th Floor, Room A12, Kolkata 700071.
LET’S TALK ABOUT YOUR PROJECT
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question?
Send your technical brief, and start a direct conversation with OSTL.