SPD RS232 (version 2)

RS232 series surge protection devices (SPDs) are manufactured while using multi-stage protection circuits. They are used to protect communication circuits that work with the RS-232 protocol. A gas-filled surge arrester is used as a rough protection in the circuits, while a transient voltage suppressor (TVS) or varistor, or a combination thereof, is used as the thin protection element.

Such a solution allows to achieve a high diverting ability, a sufficiently low threshold for the protection (SPD operating voltage) and a high response speed. The current protection stages together with isolation elements can be placed in a single compact case mounted on a DIN rail, 18 or 36 mm wide, given the relatively low discharge currents values  (when compared with power supply circuits).

SPD data are connected in series in the RS-232 interface circuit. At the same time, the protective circuit takes into account not only the permissible levels of impulse effects on the protected equipment, but also the internal features of the protected circuits and the RS-232 interface, such as a rated current of 0.5 A, a rated voltage of 24 V and a transmission speed of up to 10 Mbit /from. TVS diodes provide dissipation up to 1500 watts or up to 3000 watts of pulsed power. It is possible to connect both shielded and non-shielded lines of the RS232 interface. The device is available in versions with the ability to connect up to 4 wires of the interface line.