Choosing fibre glass sleeving for motor and transformer leads
How to select fibre glass sleeving by size, coating and temperature, and what details to give when ordering. · Updated
What it is used for
Fibre glass sleeving is a braided glass-fibre tube that adds insulation and mechanical protection to leads, connections and wire bundles in motors, transformers, heaters and appliances. Super Electrical supplies fibre glass tubes and sleeving from 0.5 mm to 25 mm, varnished and unvarnished.
How to choose
- Size: choose an inside diameter slightly larger than the wire or bundle so it slides on easily without being loose.
- Coating: unvarnished sleeving is flexible and used for heat protection; varnished or resin-coated sleeving adds dielectric strength and resists fraying; silicone-coated types stay flexible at higher temperatures.
- Temperature: match the sleeving's thermal class to the insulation class of your equipment.
- Voltage: check the manufacturer's breakdown voltage for the coated grade if the sleeving is relied on for electrical insulation.
What to send with your enquiry
- Inside diameter (or wire size)
- Coated or uncoated, and required temperature class
- Length or quantity in metres or coils
- Application
Frequently asked questions
What sizes of fibre glass sleeving are available?
Super Electrical's catalogue lists fibre glass tubes and sleeving from 0.5 mm to 25 mm, varnished and unvarnished. Other sizes can be sourced on request.
Is fibre glass sleeving an electrical insulator?
Glass fibre itself does not conduct, but uncoated braided sleeving has gaps and is mainly a thermal and mechanical protection. Varnished or silicone-coated sleeving provides a rated dielectric layer; check the grade's breakdown voltage.