<ol>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Reduced Burden: The burden offered by the static relays to the protective current and potential transformers is very less compared to that offered by the electromagnetic relays. The typical burden of electromagnetic relays ranges from 3 VA to 10 VA, whereas that of static relays is of the order of 500 millivolt-amp. Because of low burden C. T. is operated in the lower part of the linear portion of the magnetization curve of C. T. Hence problems of C. T. saturation and resulting unwanted operation of the relays are overcome. The size and cost of C. T./P. T. are reduced.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">No Moving Parts: Static relays do not use any moving element. This results in:</span></p>
	</li>
</ol>

<ul>
	<li style="text-align:justify">
	<p><span style="font-size:14px">No contact bounce.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">No arcing.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">No spring restraint.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Absence of friction.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Practically no maintenance.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Immunity to shocks and vibrations.</span></p>
	</li>
</ul>

<ol start="3">
	<li style="text-align:justify">
	<p><span style="font-size:14px">Fast Response: When the input is given to the static relay, output is available within practically no time (few nanoseconds). e. g. if emitter-base junction is forward biased in transistor, it will conduct immediately.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Better Sensitivity: The static relays can have much better sensitivity because of ease of providing amplification.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Very Small size of relays and Hence very small panel sizes.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Flexibility: A variety of functions like sensing NPS (negative phase sequence) currents (which is very much required in protection against unbalanced loading of generators and&nbsp; motors), filtering harmonics (one very important advantage of this filtering is avoiding wrong zero crossing detection in case of phase comparators), differentiation of the current or voltage signal (this differentiation reduces transient overreach of the instantaneous overcurrent relays as we will discuss later), integration etc. can be performed using static relays (which is either impossible with the use of electromagnetic relays or such functions would require very large space). The quality of protection offered, hence, by the static relays is much better as compared to their electromagnetic equivalents.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Low Resetting Time: In modern power system, fast automatic reclosing circuit breakers are used to maintain the stability of the system. When fault occurs, the circuit breaker clears the fault by receiving the signal from the protective relay. But as 85 % faults are transient, the recloser relays will close the circuit breaker after 0.3 second which is a flashover time. Within this time, the protective relay must have reset as if it is a sustained fault, resetting of the protective relay fully is a requirement for selective tripping. A static relay resets much earlier to this time (0.3 second). An electromagnetic relay takes a very long time to reset. Typical resetting time of induction disc type electromagnetic relay giving normal inverse characteristic at TMS 1.0 is around 10 seconds and that of extremely inverse IDMT overcurrent relay is of the order of 26 seconds. Hence such relays are just useless when automatic reclosing circuit breakers are used in the system.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Low Overshoot: As we have discussed earlier, the overshoot of static relays is of the order of 1 cycle as against 5 cycles in case of electromagnetic relays.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Low Transient Overreach of Instantaneous overcurrent relays.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">High drop-off to pick-up ratio.</span></p>
	</li>
</ol>