50 is the ANSI device number for an instantaneous overcurrent relay. The G suffix stands for "ground." A 50G protection relay trips the circuit breaker without time delay when it detects a ground fault on the circuit.
LBB is local breaker protection
Directionalized relays are relays that use a polarizing circuit to determine which "direction" (in the zone of protection, or out of the zone protection) a fault is. There are many different types and different polarizing methods - ground polarizing, voltage polarizing, zero sequence voltage polarizing, negative sequence polarizing, etc. The basic operation of this relay is just like any nondirectional relay, but with an added torque control - the directionalizing element. This element allows the relay to operate when it is satisfied that the fault is within the zone of protection (ie not behind where the relay is looking).
A device with an overload protection used to control a motor is an Overload Relay.
Lock out Relay is the Master Trip relay( It is a latch relay once operated we have to reset it by manual) Which is used for Generator protection,Transformer protection,Turbine protection (Fixed in indoor Panel, Standard manufacturer only making those relays) if it operated because of any fault in above the after clearing all the fault we have to reset it by hand(normally available 110Volts or 220Volts DC).
In the event of a busbar fault, the next level of protection will operate and disconnect the busbars.
No there not same
over current protection relay
LBB is local breaker protection
differential protection relay
reactance relay is used for distance protection of the transmission line....
On a 1997 Ford Contour : The Reverse Voltage Protection relay location is marked ( D1 )
50g of what ?
Directionalized relays are relays that use a polarizing circuit to determine which "direction" (in the zone of protection, or out of the zone protection) a fault is. There are many different types and different polarizing methods - ground polarizing, voltage polarizing, zero sequence voltage polarizing, negative sequence polarizing, etc. The basic operation of this relay is just like any nondirectional relay, but with an added torque control - the directionalizing element. This element allows the relay to operate when it is satisfied that the fault is within the zone of protection (ie not behind where the relay is looking).
Lithium
5 of them make 50g
A device with an overload protection used to control a motor is an Overload Relay.
An electrical device, typically incorporating an electromagnet, which is activated by a current or signal in one circuit to open or close another circuit.Based on Characteristic the protection relay can be categorized as-Definite time relaysInverse time relays with definite minimum time(IDMT)Instantaneous relays.IDMT with inst.Stepped characteristic.Programmed switches.Voltage restraint over current relay.Based on of logic the protection relay can be categorized as-Differential.Unbalance.Neutral displacement.Directional.Restricted earth fault.Over fluxing.Distance schemes.Bus bar protection.Reverse power relays.Loss of excitation.Negative phase sequence relays etc.Based on actuating parameter the protection relay can be categorized as-Current relays.Voltage relays.Frequency relays.Power relays etc.Based on application the protection relay can be categorized as-Primary relay.Backup relay.Primary relay or primary protection relay is the first line of power system protection whereas backup relay is operated only when primary relay fails to be operated during fault. Hence backup relay is slower in action than primary relay. Any relay may fail to be operated due to any of the following reasons,The protective relay itself is defective.DC Trip voltage supply to the relay is unavailable.Trip lead from relay panel to circuit breaker is disconnected.Trip coil in the circuit breaker is disconnected or defective.Current or voltage signals from CT or PT respectively is unavailable.As because backup relay operates only when primary relay fails, backup protection relay should not have anything common with primary protection relay.Some examples of Mechanical Relay are-Thermal(a) OT trip (Oil Temperature Trip) (b) WT trip (Winding Temperature Trip) (C) Bearing temp trip etc.(a) Buchholz (b) OSR (c) PRV (d) Water level Controls etc.Float typePressure switches.Mechanical interlocks.Pole discrepancy relay.