buying guide

How Insulator Glaze Colour Is Determined

Colour has no effect on electrical or mechanical performance, but ANSI grey is defined to a Munsell notation with stated tolerances.

Colour Is Not a Performance Factor

Colour is not a relevant factor for the electrical or mechanical performance of an insulator. Worldwide the most commonly used colours are grey and brown. Grey is often preferred because it has less visual impact and contrasts better against the blue of the sky, which is why it appears in the specifications of many utility companies.

The ANSI Grey Specification

ANSI standards are available only for grey and require compliance with Munsell notation 5BG7.0/0.4, with tolerances of hue plus or minus 12, from 3G to 7B, value plus or minus 0.5, and chroma from minus 0.2 to plus 0.6.

What to Put in the Purchase Order

State the colour explicitly. Our porcelain types are produced in grey and brown, and the long-rod types additionally in white. If the ANSI Munsell notation is a contract requirement, call it out in the specification rather than leaving colour as a preference.