Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

What is a Thermal Relay?Thermal relay definitionA thermal relay is defined as a device that uses unequal expansion rates of metals in a bimetallic strip to detect overcurrent conditions.Working principleThermal relays work by heating a bimetallic strip, causing it to bend and close the normally open contact, which triggers the circuit breaker.Construction of thermal relayIt consists of a bimetallic strip, metal with different expansion coefficients, a heating coil and contacts.Technical paramete

What is a Latching Relay ?Latching Relay DefinitionA latching relay is a type of relay that maintains its contact position without continuous power application, allowing for efficient control of circuits.Circuit DiagramThe latching relay circuit diagram shows how Button-1 and Button-2 control the energizing and de-energizing of the relay, respectively.Operation MechanismBy pressing Button-1, the relay is energized and remains so even after the button is released, until Button-2 is pressed.Effici

Intermediate relay self-locking secondary control circuit

The secondary control circuit of the intermediate relay self-locking1、Physical wiring diagram&Circuit diagram2、Operation principle Close QF to connect the power supply. Press the start button SB2, the coil of the intermediate relay gets electricity. The normally open contact 9-5 is closed to conduct the power supply. The intermediate relay is self-locked and the load starts to operate. Press the stop button SB1, the coil of the intermediate relay loses electricity. The normally open contact

Physical diagram of interlock of 14-pin intermediate relayThe circuit diagram of interlock for 14-pin intermediate relays

1). What is an inverse time over current relay’s characterizing feature?The length of time that the relay operates will be reduced as the fault current increases.2). Mention the most important characteristics of relay contacts. A strong construction is required. Self-cleaning (oxides break-down quickly). Corrosion- resistantis a characteristic. Low contact resistance with no strictures and no bounces. Capable of transporting rated short-term current and also rated continuous current.3). Define p