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Tran_Lap · 13-01-2009

my understanding 51 using for overcurrent protection, but the reason of overcurrent is overload, 49 is thermal relay and the reason is overload too. So, can I use one of them for overload protection? when do I use both ?

thank you

13-01-2009	#5 (permalink)
Tran_Lap Junior Member Join Date: Jan 2009 Posts: 2 Thanks: 1 Thanked 0 Times in 0 Posts	Re: 51 & 49 function relay my understanding 51 using for overcurrent protection, but the reason of overcurrent is overload, 49 is thermal relay and the reason is overload too. So, can I use one of them for overload protection? when do I use both ? thank you __________________ ------------------ You can do, Do it now Last edited by Tran_Lap; 13-01-2009 at 05:18 AM..