Discussion at Midwinter convention

W. W. Lewis: In the paper by Messrs. Conwell and Evans it is interesting to note that the only part which gives actual data, that is, Section 3, shows that the Pertersen coil functioned satisfactorily in the manner that it was intended to function, that is, as an arc suppressor. The conditions under which the arc was made were not those usually existing in practise. In the tests an are was made between switch blades with a comparatively small separation, say a couple of inches or so. Under these conditions the residual current even though small may be enough to maintain an arc. In practise the arc is usually over an insulator with 10 or 12 in. arcing distance and considerable current is required to maintain such an arc even without the neutral reactor.