| 摘要 |
A polyconductor device is connected in series with a pair of current carrying contacts of a relay switch to delay the current surge through the contacts during the closure thereof. The polyconductor device has a negative temperature-resistance characteristic such that its electrical resistance value at temperatures below a predetermined transition temperature is at least several orders of magnitude larger than its resistance value at temperatures above the transition temperature. When the contacts are initially closed, only a small electric current passes through the polyconductor device which is in its high resistance state. After a predetermined time, the current heats the device to a critical temperature at which time polyconductor device switches to its low resistance state and the current flows essentially unimpeded thereby. During the heat-up time the contacts of the relay switch have completed bouncing and are in a stable, closed condition.
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