Iron chip is the main 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 outside. 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.

The clamp is used to clamp the iron chip, 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 may cause intermittent breakdown discharge of the iron chip and clip to ground, and the iron core and clip may form a floating potential of the iron chip after being grounded at one point. But when the iron core and the clamp are grounded at two or more points, the uneven potential between the iron core and the clamp will form a circulating current between the grounding points, and form a multi-point grounding heating problem for the iron chip and clamp.

The grounding fault of the iron chip of the transformer can cause overheating of the iron core part. In severe cases, the temperature rise of the iron core part increases, 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, causing increased iron loss and seriously affecting the function and normal operation of the transformer, to the point where 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/