SWITCHING APPARATUS FOR ELECTRIC CIRCUIT SECTION MAINLY FOR EXPLOSION HAZARDOUS ZONES Russian patent published in 2015 - IPC H01H9/30 

FIELD: electricity.

SUBSTANCE: switching apparatus for an electric circuit section mainly for explosion hazardous zones with a power supply source consists of two switching elements capable of movement towards each other and complete with contact plates at opposite ends of the elements in the direction of their movement and output conductors. In one conductor in series of the current passage there is a variable resistor, a current meter and one contact plate of the above contact. At that the second conductor is connected to the second contact plate of the contact and the variable resistor is complete with a regulator and indicator indicating limit values. The variable resistor may be made as a rheostat or a gate-controlled thyristor and before switching it is brought to the maximum value of resistance up to 10¹⁵ Ohm.

EFFECT: increased operational safety in explosion hazardous zones due to prevented spark producing in the switching process.

5 cl, 1 dwg