The Edco SPA-60B Series is an economical method of protecting circuitry associated with 120VAC interconnect signal lines commonly used in traffic control systems. In the presence of normal interconnect line voltage and frequency (60Hz), the Edco SPA-60B Series possesses the ideal characteristics of high impedance across the protector and no impedance in series with the line. In the presence of transients, the protector appears as very low impedance, thereby shunting the surge to ground.
The product is offered in two variations. The SPA-60BS protects one circuit and consists of one lead and a stud (also used for mounting). The SPA-60BS-2 is identical except it protects two circuits and consists of two leads and a stud.