ABSTRACT
In a.c. circuits the polarity of the contacts at opening is a random event and in general little transfer is usually observed, however, if the contacts are unsymmetrical (made of two different types of materials) net transfer from one contact to the other may be observed (42,43). Net material transfer in a.c. circuits may also occur if the switch had a preferred point-on-wave (POW), in which case the polarity of the electrodes is fixed, this would be similar to DC erosion.
