| 摘要 |
<p>An electro-fusion fitting e.g. for joining plastics pipes, comprises a thermoplastics body (1) a heating coil (2), main terminals (3, 4) for supplying electric current to the coil, and coding resistor (7) enabling automatic identification of the fitting to determine the electric power to be supplied to the heating coil, the resistor being electrically isolated from the heating coil and connected between a pair of auxiliary pin terminals (8, 9). A connector plug (figs. 4 to 7, not shown) for coupling the fitting to the electric current supply and control equipment is adapted to allow automatic preliminary checks for good contact between the current supply cables and the main terminals, and for the plug being properly engaged with the fitting. <IMAGE></p> |
