Quick Answer: What Is A 50 51 Relay?

What is a 86 relay?

Lock out relay is an electromechanical relay which latches its output contact.

As the name suggests, this relay once operated locks out the circuit.

Locking out means that circuit cannot be normalized until and unless this relay is reset.

This relay is also known as Master Trip Relay and its ANSI code is 86..

What do relay numbers mean?

Numbers of a Relay 85 and 86 are the coil pins while 30, 87, and 87a are the switch pins. 87 and 87a are the two contacts to which 30 will connect.

What is a MHO relay?

A mho Relay is a high-speed relay and is also known as the admittance relay. In this relay operating torque is obtained by the volt-amperes element and the controlling element is developed due to the voltage element. It means a mho relay is a voltage controlled directional relay.

What is an 87 relay?

on Differential Protection Relay [87]: Differential Protective Relay is a protective relay that functions on a percentage or phase angle or other quantitative difference of two currents. Differential relaying provides selectivity by providing a zone of protection with a circuit of interconnected CT’s.

What is 50n protection?

Earth fault protection based on measured or calculated residual current values: ANSI 50N/51N: residual current calculated or measured by 3 phase current sensors. ANSI 50G/51G: residual current measured directly by a specific sensor.

What is TCS relay?

The supervision relay type TCS is intended for a continuous supervision of circuit breaker trip circuit and to give an alarm for loss of auxiliary supply, faults on the trip-coil or its wires independent of the breaker position, faults on the breaker auxiliary contacts and faults in the supervision relay itself.

What is 67n protection?

ANSI 67N/67NC type 2. Directional overcurrent protection for impedance and solidly earthed systems, based on measured or calculated residual current. It comprises an earth fault function associated with direction detection, and picks up if the earth fault function in the chosen direction (line or busbar) is activated.

How do I set up an overcurrent relay?

Calculation of Over Current Relay Setting:Over Load Current (In) = Feeder Load Current X Relay setting = 384 X 125% =480 Amp.Required Over Load Relay Plug Setting= Over Load Current (In) / CT Primary Current.Required Over Load Relay Plug Setting = 480 / 600 = 0.8.More items…•

What is a 52 device?

52 – AC circuit breaker. 52a – AC circuit breaker position (contact open when circuit breaker open) 52b – AC circuit breaker position (contact closed when circuit breaker open) 53 – Exciter or Dc Generator Relay. 54 – Turning Gear Engaging Device.

What is 85 on a relay?

85 and 86 are the coil pins while 30, 87, and 87a are the contact pins. … Realizing that 85 and 86 are the coil pins, these pins will be transferring the current through the coil. 85 will be used to ground your relay, while 86 will be connected to the switchable power.

What is 64r relay?

Rotor earth fault relay 64R which is used to protect the generator or alternator rotor against earth fault (the short circuit between rotor’s winding to ground). It senses the alternator’s rotor earth leakage current. The ANSI code for rotor earth fault relay is 64R.

What’s a relay switch?

Relays are electric switches that use electromagnetism to convert small electrical stimuli into larger currents. These conversions occur when electrical inputs activate electromagnets to either form or break existing circuits.

Which type of relay is used in substation?

The numeric relays are mostly used in the generating stations and substations for automated protection. These relay can protect various components such as feeder, Motor, Generator, Transmission line, Transformers and Bus bars.

How does a 50 51 relay work?

On electromechanical relays, the 50 function can be added as an instantaneous attachment to a 51 time-overcurrent relay. If a relay has both 50 and 51 functions present and enabled is referred to as a 50/51 relay. Typically, overcurrent relays are employed as one per phase.

What is a 59 relay?

59 – Overvoltage Relay 60 – Voltage or Current Balance Relay. 62 – Time-Delay Stopping or Opening Relay. 63 – Pressure Switch. 64 – Ground Detector Relay. 65 – Governor.

What is a 52 relay?

52 AC circuit breaker A device that is used to close and interrupt an AC power circuit under normal conditions or to interrupt this circuit under fault or emergency conditions. … 55 Power factor relay A relay that operates when the power factor in an AC circuit rises above or falls below a predetermined value.

What is a master relay?

What is a Master Trip Relay? Defination: Master trip relay is a contact multiplication or an Auxillary relay, which operates on the command from Multiple protection relays and gives a Single Commmand to the Breaker Trip Coil.