Protection has assumed a large importance in the power industry in the recent years. This protection involves the use of relays on a large scale. Relays are basically used to give commands to circuit breakers, contactors, etc by sensing different parameters like current, voltage, etc. Just as electrical circuits may range from a few watts to 100 megawatts, the size and rating of the relays vary considerably. Study of relays is now being included in the engineering curriculum. M/S SCR Elektroniks have developed demonstration units for different types of relays such as under protection/over protection relay, temperature protection relay, motor protection relays, AC/DC relays and contactors keeping the engineering curriculum in view.
Suitable enclosure with stand and work space
Can test two types of relays in a single system
Neat display with lamps and metering
Module I - 1. Under / Over voltage : HLVD2 Minilec relay, with mounting arrangement with stand supply voltage 415 V; Aux. Supply voltage 220 V AC.
Module II - 1. Three Phase variable voltage source each phase adjustable from 0 to 270 (4A max) 2. Phase reversal switch. 3. ON/OFF switch for each phase. 4. 3 & 1/2 digit Voltmeter (0-500 V) with selector switch for 3 phase. 5. Relay will operate a contactor of 12A, 220V AC. 6. Input supply cable of 5 meters 3 ph, 4 core, 12 A capacity. 7. Input protection by MCB of 15 A rating. 8. Demonstrative enclosure with stand. 9. Digital time interval 4 digits (SCR/scot ut make), with reset switch wired with relay & contactor. 10. Three Phase, 2 HP, 1450 RPM Inductor Motor.
The test bench is generally offered as a standard issue, but can be designed as per the customer specs
The under / overvoltage condition is simulated using a simple variable transformer and under voltage and overvoltage relay functionality and working is demonstrated