(a) The percentage or portion of wire on a dynamo or motor armature that does not concur in the production of electromotive force. The dead-turns, q. v., of a drum armature or the inside wire in a Gramme ring armature are dead wire. (b) A disused and abandoned electric conductor, such as a telegraph wire. [...]

In the winding of an armature, a given percentage of the turns, it may be 80 per cent., more or less, is assumed to be active; the other 20 per cent. or thereabouts, is called dead-turns. This portion represents the wire on such portions of the armature as comes virtually outside of the magnetic field. [...]

A two-phase alternator of the ordinary type connected as a motor to another alternator cannot start itself, as it has dead points where the relations and polarity of field and armature are such that there is no torque or turning power.

A fault in a telegraph line which consists in the wire being thoroughly grounded or connected to the earth.

Reaching its reading quickly; applied to instruments having a moving indicator, which normally would oscillate back and forth a number of times before reaching its reading were it not prevented by damping.

A cylinder and piston, the latter loosely fitting or perforated, or some equivalent means being provided to permit movement. The cylinder may contain a liquid such as glycerine, or air only. Thus the piston is perfectly free to move, but any oscillations are damped. In some arc lamps the carbon holder is connected to a [...]

Preventing the indicator of an instrument from oscillating in virtue of its own inertia or elasticity. In a galvanometer it is defined as resistance to quick vibrations of the needle, in consequence of which it is rapidly brought to rest when deflected (Ayrton). In dead-beat galvanometers damping is desirable in order to bring the needle [...]

(a) A copper frame on which the wire in a galvanometer is sometimes coiled, which acts to damp the oscillations of the needle. (b) A tube of brass or copper placed between the primary and secondary coils of an induction coil. It cuts off induction and diminishes the current and potential of the secondary circuit. [...]