ELECTRONIC RELAY WITH TRANSFORMER ISOLATION AND PROTECTION FROM CURRENT OVERLOAD Russian patent published in 2009 - IPC H03K17/60 H01H81/00 

FIELD: electronics.

SUBSTANCE: invention relates to electronic engineering and may be used in switching systems with galvanic isolation and overload protection by current. According to the invention, transformer isolation has to be implemented by protecting relay from current overloads both in transient mode when load is switched on, and in stabilised conditions and enabling control of protection parameters depending on load parametres. In order resolve to the above mentioned task, in addition to pulse generator, pulse transformer, rectifying diode, filter capacitor and electronic switch in electronic relay with transformer isolation, the filter capacitor, discharge resistor, stabilised voltage source, load current sensor, operating amplifier, relay element, reference input element for relay element, integrating element and "latch" consisting of n-p-n and p-n-p transistors and load resistor are included in transistor. Time of protection from current surges during load switching is proportional to the integrating element capacity. Threshold of protection actuation may be adjusted changing resistance in reference input element of relay element.

EFFECT: wide functional possibilities of electronic relay.

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