Questions about the Time Delay

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David
Posts: 219
Joined: Sun Oct 04, 2015 6:18 pm

Re: Questions about the Time Delay

Post by David » Wed Jun 28, 2017 4:02 pm

a) Yes, quite OK to remove switch and connect 4700uF to pins 6 & 7 and the pot.
b) The easiest way is to connect a led in series with a 1k to 1.5k resistor from pin 3 to ground. The led will light up when the coil of the relay is energised. BTW, it is usually good practice to connect a diode (1N4000 or similar) across the relay coil with the anode to ground and the cathode to pin 3. This is to suppress the back emf spike when the relay de-energises. Take care with getting the diode in the right way round!

Hope this helps.

ThomasRes
Posts: 1
Joined: Wed Oct 11, 2017 10:16 am

Re: Questions about the Time Delay

Post by ThomasRes » Sun Oct 22, 2017 4:15 pm

David wrote: Wed Jun 28, 2017 4:02 pm a) Yes, quite OK to take TestRX and connect 4700uF to pins 6 & 7 and the pot.
b) The easiest way is to connect a led in series with a 1k to 1.5k resistor from pin 3 to ground. The led will light up when the coil of the relay is energised. BTW, it is usually good practice to connect a diode (1N4000 or similar) across the relay coil with the anode to ground and the cathode to pin 3. This is to suppress the back emf spike when the relay de-energises. Take care with getting the diode in the right way round!

Hope this helps.
I never knew you could safely remove switch and connect 4700uF to pins 6 & 7. Thanks for the info David.

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