Gelco electronics supplies motor guard relays. These motor guard relays are basically current sensing single phasing preventers, which gives total protection to three phase ac electric motors. The basic principle of the operation behind this motor guard relays is sensing negative sequence current components. These relays trip electric motor starter as soon as they exceed the dangerous level. They offer protections up to the motor terminals and are un defective to the motor back emf. The motor guard relays are available in two models, namely mgr and mgr-c. Both models are almost same with slight difference in features, like under/over-voltage protection and inverse time current characteristic setting. These models offer total protection against single phasing on supply side as well as the motor side. Overloading [inversely time current characteristics] reverse supply, current unbalance and high/low voltage, auto/manual reset provision, etc. Is also provided. Enclosures are made from high impact polystyrene moulded with nylon-moulded connection strip. These are available up to 200 a. Green led indicates spp healthy condition and red led indicates overloading condition. Both models offer single phasing protection even if the motor is on no-load. Physical specification of the motor guard relays includes it weighs around 750gms and their overall dimensions 140mm x 100mm x 95mm.
