What is the time of operation for 0.5 TMS If the time operation of a relay for unity TMS is 10 SEC?

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The operating time of an electrical relay mainly depends upon two factors : How long distance to be traveled by the moving parts of the relay for closing relay contacts and How fast the moving parts of the relay cover this distance. So far adjusting relay operating time, both of the factors to be adjusted. The adjustment of travelling distance of an electromechanical relay is commonly known as time setting. This adjustment is commonly known as time setting multiplier of relay. The time setting dial is calibrated from 0 to 1 in steps 0.05 sec. But by adjusting only time setting multiplier, we can not set the actual time of operation of an electrical relay. As we already said, the time of operation also depends upon the speed of operation. The speed of moving parts of relay depends upon the force due to current in the relay coil. Hence, it is clear that, speed of operation of an electrical relay depends upon the level of fault current. In other words, time of operation of relay depends upon plug setting multiplier. The relation between time of operation and plug setting multiplier is plotted on a graph paper and this is known as time / PSM graph. From this graph one can determine, the total time taken by the moving parts of an electromechanical relay, to complete its total travelling distance for different PSM. In time setting multiplier, this total travelling distance is divided and calibrated from 0 to 1 in steps of 0.05. So when time setting is 0.1, the moving parts of the relay has to travel only 0.1 times of the total travelling distance, to close the contact of the relay. So, if we get total operating time of the relay for a particular PSM from time / PSM graph and if we multiply that time with the time setting multiplier, we will get, actual time of operation of relay for said PSM and TSM. For getting clear idea, let us have a practical example. Say a relay has time setting 0.1 and you have to calculate actual time of operation for PSM 10. From time / PSM graph of the relay as shown below, we can see the total operating time of the relay is 3 seconds. That means, the moving parts of the relay take total 3 seconds to travel 100 % travelling distance. As the time setting multiplier is 0.1 here, actually the moving parts of the relay have to travel only 0.1 x 100% or 10% of the total travel distance, to close the relay contacts. Hence, actual operating time of the relay is 3 x0.1 = 0.3 sec. i.e. 10% of 3 sec. https://www.electrical4u.com/pick-up-current-current-setting-plug-setting-multiplier-and-time-setting-multiplier-of-relay/*##**##*