Method for measuring the welding voltage in a heating coil of a heating coil fitting and heating coil welding apparatus therefore

摘要

Welding current is supplied via connecting lines (20) and connectors (22) to the connectors (14) of the heating coil. Actual welding voltage is measured at the contact points of both coil connectors to eliminate corrosion-induced errors. Measurements are made with a measuring line (26) and tip (24) electrically isolated from the current supply lines (20) and their connectors to counteract any effects from the latter. An Independent claim is made for the heating coil welding system for the process in which each current supply connector (22) includes a voltage measuring tip (24) and measuring line (26) which are isolated from the main voltage supply lines (20) and can make a non-permanent connection with a tubular contact (14a) of the coil connector (14).