Issuing body: IEC
IEC 60664-1
Insulation coordination — clearance and creepage
IEC 60664-1 sets insulation coordination for equipment within low-voltage systems. Clearance is derived from the rated impulse withstand voltage together with pollution degree and altitude; creepage from working voltage, pollution degree and the comparative tracking index of the insulating material. This is the standard underneath the clearance and creepage provisions that IEC 61439 applies to an assembly. It is also where busbar edge geometry becomes an electrical question rather than a handling one: a sharp corner concentrates the electric field, and a radiused edge distributes it more evenly at the same creepage distance.
Technical background
Materials and finishing
Busbar chamfering and edge radius
Why busbar edges are radiused R2 to R10, what IEC 60664-1 field homogeneity actually requires, and why IEC 61439 does not mandate chamfering.
Materials and finishing
Fabricating busbars for EV charging equipment
Thin-gauge, high-mix EV charging busbar work: why edge radius and burr control decide insulation life, and what fast changeover demands of the machine.
Standards and compliance
Processes