Issue:
Requests for Vacuum Pressure Impregnation (VPI) on Low Voltage Transformers

Product Line:
LV Transformers

Environment:
Applies to Low Voltage Transformers by SquareD/Schneider Electric

Cause:
VPI is a Transformer coil insulating technique usually used on Medium Voltage Transformers

Resolution:
No. Square D completely immerses its core and coil assemblies in a UL recognized 220C varnish.
VPI systems are used to impregnate Medium Voltage units to fill the voids to prevent build up of Ozone in the winding spaces during normal operation. It is also used on small, fractional VA units that need to fill the voids to accommodate heat transfer. On the larger LVGP units neither of these conditions apply so SquareD/Schneider Electric uses a varnish dip/bake process. Many companies have the VPI system installed, use it for all their Transformers and put it in their specification as a exclusionary tool

Publicado para:Schneider Electric Mexico