Transformers generate a brief peak current when starting up, which is referred to as the inrush current. While this is a very brief event it can result in a protective device (a fuse or circuit breaker) tripping when the transformer starts up. You can find more information on this here in our FAQ.

One solution EREA can supply involves our inrush current limiters. These devices ensure that the transformer starts up gently. They then switch off automatically.

On a single-phase transformer a single inrush current limiter will suffice, while three will be required for a three-phase transformer. A circuit diagram can be found via this link.

You can find which inrush current limiter is suitable for your transformer here.

Our inrush current limiters can be used for transformers with a nominal line current up to 25A. For larger transformers we have developed the IRC series. These transformers are designed with an inherently low inrush current.