DTDW series Dry Type Transformers are 3 phase, indoor, insusceptibility to moisture and compact designed for general application when ever voltage conversion and/or electrical isolation are required. Its can also be use to provide protection against noise and transient in the common modes.
Cold rolled, oriented grain steel sheet with low specific losses, insulated on both sides by thin organic coating.
- Copper Strips with Class F (155oC) or Class H (180oC) enameled coated.
- Class H(NOMEX) Insulation material is used between overlapping turns or layers.
- Axial channels are used between layers of primary and secondary winding to provide air gap for uniform cooling.
- High temperature tolerant fiberglass boards are used as bobbins to separate the core and windings.
- Sized, transposed and shaped to minimize Eddy current losses.
- Vacuum impregnated with class H varnish and oven dried.
Low Inrush Current
Special design measures are implemented to reduce the inrush current, such as primary winding at outer layers to increase resistance high grade iron core with high saturation to prevent core saturation during startup.
- Insulation Test at 1000Vdc and
- Hi-potential test at 2.5KV
- Resistance Test
- Open circuit Test (No-load Test)
- Short circuit Test
- Temperature Rise Test
- Noise Level Test