The iron chip is the primary magnetic circuit part in transformers, usually made up of hot-rolled or cold-rolled silicon steel sheets with high silicon content and coated with insulating paint on the surface. The iron chip and the coil wound around it form a complete electromagnetic induction system. The transmission power of a power transformer depends on the material and cross-sectional area of the iron chip.

Clamp is used to clamp iron chips, and small support plates can be soldered onto the clamp to fix the wooden components of the lead wires. The position of the clamp is on both sides of the iron yoke above and below the iron chip. During normal operation of power transformers, the iron chips and clamps should have a reliable grounding.

If there is no grounding, the floating voltage of the iron chip and clip to ground will cause intermittent breakdown discharge of the iron chip and clip to ground, and the possibility of forming the floating potential of the iron chip will be eliminated after the iron core and clip are grounded at one point. But when the iron core and clamp are grounded at two or more points, the uneven potential between the iron core and clamp will form a circulating current between the grounding points, and cause multi-point grounding heating problems for the iron chip and clamp.

The grounding fault of the iron chip of the transformer can cause overheating of the iron core. In severe cases, the temperature rise of the iron core will increase, causing light gas action, and even leading to tripping due to heavy gas action. The melted iron chips form a short circuit between the iron chips, which increases the iron loss and seriously affects the performance and normal operation of the transformer. Therefore, it is necessary to replace the iron core silicon steel sheets for repair. So the iron chips and clamps of transformers are not allowed to have multiple grounding points, and only one grounding point is allowed.

Article source: Transformer silicon steel sheethttp://www.cheungshun.com/