What is Relay?
A relay is an Electro-Mechanical switch that changes a low release current into mechanical movement. A polarized relay consists of a soft-magnetic circuit formed by an Armature and a Yoke as shown in above fig.
Relay components for machine safety
Auxiliary relays are used for machine safety. Auxiliary relay assists a protective relay in switch-gear for a number of operations. Protective Relay performs task of measurement and under required conditions, is closes its contacts. Protective relay is relieved of all duties such as tripping, Time lag, breaking of trip circuit current, giving alarm, showing flags,etc. This duties are performed by Auxiliary Relays.Each of these duties are performed by an auxiliary relay.Seal-in Relay, Alarm Relay,Time lag Relay are some of the auxiliary relays.
Contacts of Protective relay are delicate. Seal-in Relay is an auxiliary relay that protects the contacts of Protective relay. Alarm Relay is an auxiliary relay that gives trip alarm(Indication) both in audible and visual form.
Time lag relays are auxiliary relay that operate after a preset time lag. They are used in control and alarm circuits to allow time for the required sequence of operation to take place. This are various applications of auxiliary relay.
These parts are made of 48% Ni:Fe.PML provides these parts with high magnetic properties and critical dimensions maintained for proper working of the auxiliary relay.