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A motor that burns out after one season, a transformer that runs hot, a rewound pump that fails within months: in most cases the problem is not the workmanship, it is the winding wire. Cheap or poorly made enamelled copper wire can have thin insulation, weak copper or hidden pinholes, and every one of those shows up as a failure later, on your customer's site, with your name on the job.
This guide is for the people who work with copper every day in Nepal: motor winders, electric wire and hardware shops, transformer manufacturers and transformer repair workshops. It explains how to choose enamelled copper wire and copper strip, what the specifications mean, and what to check before you buy. It is written by BN Mahto Group, a Nepal-based manufacturer of electrical products since 1987.
Why the quality of copper and enamel matters
A winding has two jobs. The copper carries current with as little loss as possible, and the enamel insulation keeps each turn separate from the next. If either one is weak, the winding fails.
- Pure copper means lower losses. Good winding wire uses high-conductivity electrolytic copper. Impure or undersized copper has higher resistance, which means more heat, more energy loss and a shorter winding life.
- Even enamel means fewer short circuits. Thin or uneven enamel, or pinholes in the coating, lets neighbouring turns touch. That causes inter-turn short circuits, the most common reason rewound motors burn out.
- The right thermal class means survival under load. Insulation rated for too low a temperature softens and cracks in a hot motor or transformer.
- Accurate diameter means a proper fit. Wire that is thinner than its stated size cannot carry the rated current and will overheat, even if it looks right on the spool.
Enamelled copper wire: know your types
Enamelled (magnet or winding) wire is bare copper coated with a thin layer of insulating varnish. The main differences are the enamel type and its temperature rating.
conductor resistance, insulation High Voltage breakdown, Elongation flexibility, heat resistance and Mendral winding test methods.
- Consistent supply
- A range that fits the trade. Enamelled copper wire in multiple sizes, plus copper strip for transformers and heavy-current work, so winders, shops and manufacturers can source from one place.
- Straight advice. Our team can help you pick the class, size and quantity for your job. Tell us what you are winding and we will recommend what suits.
- Trade-friendly buying. special discount in bulk Buying, Bonous available, Credit Against bank Gurantee for regular customer
- Delivery across Nepal. All over Nepal.
How to order
Send us the following and we will reply with a quotation:
- Product: enamelled copper wire or copper strip
- Size: SWG or diameter in mm for wire; thickness and width for strip
- Type: thermal class, enamel grade, bare or covered
- Quantity: in kg or number of spools
- Delivery location and date
Call or message our copper sales team: phone and WhatsApp 9801622233 Email: info@bnmahatogroup Visit: Enamelled Copper Wire | Copper Strip | Download our catalogue | Contact us
Frequently asked questions
What is the difference between enamelled copper wire and ordinary copper wire? Enamelled wire is bare copper coated with a thin insulating layer, so turns can be wound tightly side by side without touching. Ordinary insulated cable has a much thicker plastic covering and is meant for wiring, not for windings.
Which thermal class should I choose for motor rewinding? Match or exceed the class of the original winding. Class F (155 °C) is common for industrial motors and pumps, while Class H (180 °C) suits heavy-duty or hot environments. When unsure, ask us and describe the machine.
What does SWG mean on copper wire? SWG is Standard Wire Gauge, a numbering system for wire thickness. A higher SWG number means thinner wire. Always confirm the diameter in mm, since tolerances and labelling vary between suppliers.
Can I use copper strip instead of round wire? Yes, where current is high. Strip packs more compactly and carries heavy current well, which is why it is used in transformer low-voltage windings. For small motors and light-current coils, round wire is usually more practical.
What is the price of enamelled copper wire in Nepal? Price depends on the copper market, wire size, thermal class and quantity, and changes often. Send us your requirement for a current quotation.
Do you supply small shops as well as manufacturers? Yes. We supply winders, electrical shops, workshops and manufacturers.
Is aluminium winding wire a good substitute? Aluminium is lighter and cheaper but has lower conductivity and needs a larger cross-section for the same current. For motors and repairs where the original winding was copper, rewinding in copper is the safer way to maintain performance.
Conclusion
Winding wire is a small part of the cost of a motor or transformer, but it decides whether the machine lasts. Choose the right thermal class, measure what you buy, insist on test evidence, and work with a supplier who stands behind the product.
Ready to buy? Request a quotation from Elex Wire today. Tell us what you are winding and we will help you choose the right enamelled copper wire or copper strip.