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Relay switching

I am trying to switch on and off LED's with the help of a relay.

The relay I am using is 24VDC SPDT relay and the LED is 12VDC LED.

When I switch on the 12V supply the yellow LED should glow since the relay is in normally closed condition[please refer the schematic] and when the 24V supply is turned on the relay gets activated and becomes normally open thus allowing the flow of current to turn on the red led. Eventually, cutting of the supply to the yellow led.

When testing this circuit on a breadboard, the yellow is turning on when 12V supply is given and when I turn on the 24V supply, the relay gets activated but the red led is not glowing. When I measured the voltage near the led[supposed to be 12V], it is not getting any supply itself. I am stuck at this point and don't know if I am missing any small thing here.

The relay I am using is G5LE-1-E DC24 RELAY GEN PURPOSE SPDT 16A 24V.

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  • \$\begingroup\$ it's very unusual to switch LEDs with relays. It's even more unusual to use a 24 V-driven relay to drive a 12 V LED (which, by the way, is an LED + built-in resistor). Have you taken into account that LEDs don't work in both directions? \$\endgroup\$ – Marcus Müller Apr 12 '17 at 14:10
  • \$\begingroup\$ This schematic is only a part of a circuit.I had to use 24V supply. so using a 24V relay to act as a switch between red and yellow led. By the way, those are two separate led's only the Negative of both led is connected to ground of 12V. Thank you. \$\endgroup\$ – user3323976 Apr 12 '17 at 14:20
  • \$\begingroup\$ Have you got the relay contacts the wrong around? The common connection should always be at 12V with the NO and NC contacts being switched over. \$\endgroup\$ – JIm Dearden Apr 12 '17 at 14:24
  • \$\begingroup\$ I checked the contacts too. Its the same way you mentioned. \$\endgroup\$ – user3323976 Apr 12 '17 at 14:29
  • \$\begingroup\$ " when I turn on the 24V supply, the relay gets activated but the red led is not glowing" does the Yellow LED turn off? \$\endgroup\$ – Tyler Apr 12 '17 at 14:47

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