Mutual inductors

The structural characteristic of an instrument transformer is that coils, iron cores, and metal conductors are cured with epoxy resin through vacuum casting or APG (Automatic Pressure
Gelation) process. Epoxy resin has a high modulus and brittleness, and there is a significant difference in linear expansion coefficient between epoxy resin and metal coils/conductors.
During the thermosetting molding process, factors such as curing shrinkage, environmental temperature variation, and temperature rise caused by electrical load, leading to epoxy cast transformers being subjected to multi-dimensional coupled stress, which is prone to product cracking and damage, as well as insulator life degradation induced by mechanical, electrical, and thermal factors; cast dry-type transformers thus face reliability risks. The quality of epoxy resin is one of the key factors to address these risks.
Epoxy resin for transformer products is required to have low viscosity and good fluidity; excellent low-temperature resistance, strong crack resistance, superior electrical performance, and low partial discharge, while also possessing good environmental friendliness.

Xrun APG Casting Epoxy Resin for Instrument Transformers