PrismaSeT I System M switchboard comply with the IEC 61439-1/2 edition 2 requirements. Insulation by sleeves for busbars is not recommended and it is not a standard solution in PrismaSeT switchboard. All the panels which are type tested are with bare busbars.
Heat shrinkable sheathing temperature is usually limited to 105°C. Over this temperature limit, heat shrinkable sheathing tends to crack (self-constraint due to its heat-shrinkable feature). When cracking, over time, this insulation material may create a creepage way between two phases, thus potentially generating phase to phase flashover (internal arc).