EK Technologies

  TELE-SWITCHING (TELESWITCH) 1. FUNCTION OF A TELE-SWITCH A tele-switch is an electromagnetic device used to control a lamp or many lamps from different positions. A tele-switch can also be called a teleruptor. Example: Control of a lamp from three positions, stair-case, long corridors. 2. ARCHITECTURAL DIAGRAM OF A TELESWITCH Case study : Hall Architectural diagram of a teleswitch 3. CIRCUIT DIAGRAM OF TELESWITCH   We distinguish two circuits: -       The command circuitry: The coil is supplied through the impulse from the push buttons. -       The utilization circuit: the contact « k » of tele-switch controls the lamps. Circuit diagram of a teleswitch 3.1. OPERATION OF A TELE SWITCH – The first impulse supplies the coil K and actions the contact   « k ».   – A second impulse supplies the coil K opens the contact    « k ». REMARK: The control circuit ...

ELCB AND RCCB (RCD) Earth Leakage Circuit Breaker (ELCB) Working Principle of ELCB An Earth Leakage Circuit Breaker (ELCB) is a security device used in an electrical installation to detect leakage current and protect humans against the risk of an electric shock, from this leakage current. The operation is such that, the power supply connected at its switching terminal (contact of the circuit breaker) is disconnected by a special type of latching relay when it detects a leakage current. Thereby, protecting individuals getting in contact with this leakage current against the risk of an electric shock. This circuit breaker remains OFF until reset manually. Types of Earth Leakage Circuit Breaker They are two types of Earth Leakage Circuit Breakers. They are named based on their principle of operation. They are; The Voltage Earth Leakage Device (Known as the ELCB) and The Current Earth Leakage Circuit Breaker (RCD or RCCB). In the past, when referring to Earth Lea...

PAST GCE QUESTIONS TVE FOR POWER ELECTRONICS CAMEROON GENERAL CERTIFICATE OF EDUCATION BOARD Technical and Vocational Education Examinations Electrical Power Systems EPS (F3) Note here that the years will not be disclosed.  These are the most recent years past questions. SETTINGS 1 1.                The circuit of figure 1 can be referred to as that of A voltage step down B current step down C voltage step up D current step up _________________________________________ 2.            DIACs are specifically designed to trigger; A TRIACs B Thyristors C GTO D TRIACs and Thyristors _______________________________________________ 3.            A thyristor can...