This standard is intended to aid air switch users in establishing suggested maximum values of excitation, resisted and capacitive currents that may be successfully interrupted while using outdoor air switches. This guide pertains to air switches mounted in the normal horizontal-upright position and not equipped with interrupting aids. (Superseded by IEEE Std C37.30.1-2011)

This guide is intended to provide air switch users with a means for determining the magnitude of excitation as well as resistive and capacitive currents that may be successfully interrupted with horn-gap, vertical-break air switches in outdoor locations mounted in the normal horizontal-upright position and not equipped with interrupting aids. The minimum centerline-to-centerline phase spacing of each switch is based upon dimensions stated in ANSIC37.32-1972 [B1]1 , Table 5, Column 6. This guide assumes that the switches are applied to an effectively grounded wye system. A guide for ungrounded systems is being considered.