Indoor post insulators are used in indoor power stations with rated voltages of 6~35kV, power distribution units and electrical equipment for substation to insulate and fix conductive parts.

The insulator is suitable for the ambient temperature of -40 ° C ~ +40 ° C, the installation location altitude is not more than 1000 m, the high prototype is not more than 4000 m

The insulators are divided into three types of outer plastic, inner and combined plastic according to the plastic structure. The insulators are classified according to the rated voltage and bending strength level as follows:

The main body structure of the insulator porcelain has a cavity partition (breakable) structure and a solid (non-breakable) structure. Joint glued post insulators are generally solid, non-breakable structures. The latter structure improves safety and reliability and reduces maintenance test workload compared to the former structure.

The inner plastic binding structure, because the metal accessories are glued into the porcelain hole, correspondingly increases the insulation distance, improves the electrical performance, and also reduces the space occupied by the installation, but because the inner plastic binding is unfavorable for improving the mechanical strength, Insulators with higher mechanical strength requirements should be combined with plastic (ie, the upper attachment is glued inside and the lower attachment is externally glued).