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How is a 555 12V delay relay timer wired? Answered

I purchased several simple 1-channel relay timers (single pot), followed online videos to use but I could not get them to function properly. Can anyone tell me, in clear detail, how to connect/wire them. I also purchased several other types of relay timers (double pot), much like the Vellman MK111 interval timer, these worked fine.
Clearly I'm doing something wrong.


Click the pic to see the whole image..

Thank you for responding and being prompt with it.
I think my problem is less with understanding the 555 and more with getting the relay to relay. (function as intended)
I've seen some of the demos using relays and it seems pretty straight forward, but apparently I'm missing it. I'm hoping to find clear instructions on the what/where the connections are attached at the relay and the load. I've tried about 4 - 5 relays and can not get any of them to do what they are supposed to. So, clearly I'm missing something.
Thanks again.

The relay coil voltage must be the same as the 555 voltage and activate under 300 ma.. Here are some relays and pinouts.

It helps too visualize how the wiper moves as in the second picture.

You may have to click the pic to see a whole image

5V DPDT relaySHAPE.pngDPDTopenRelay .jpgDPDT Relay.jpg


I sent a couple pics of what I have, hopefully will better explain what I'm after.

I just need to know how to connect them to the devices I will use them with. I seen some online pics of their use. I'm getting it wrong when I follow them. Part of the problem is I can't find anything that tells me where to connect what wire to where. (being the novice that I am)

Thanks mucho. cgc

relay pic 2.jpgrelay pic 1.jpg

I think what you need to do is take an ohmmeter and measure from one terminal to another until you find two that are about 250 ohms resistance for a relay with a 12 volt coil. If you want to figure out the amount of current at 12v needed to energize the coil you simply divide 12 volts by the resistance of the coil in ohms. In this case, the minimum current that you need to energize the coil is 48 milliamps. You can drive a small relay like this directly from the 555. If you want to drive larger relays with lower resistance coils you will need to drive a Mosfet or power bipolar transistor. There are lots of examples of this on the web.


You connect the coil (which has to be the correct working voltage for the 555 timer) to the timer ?

It would help if you posted an example of what you have.


Thank you for replying.

I apologize for not responding to your pic request sooner. I had a personal issue that has consumed much of my time and as easy as it is to send pics But, from some of the other replies and pics posted in response to my request for help I think I should revise my question. Iceng sent a pic of just a relay unit and talked about things beyond what I think I need to know. I followed some pics I saw online of how to use the relays I have, but apparently missed something. I have not been able to get them to work the way they are supposed to. Hpics of the relay timers I bought

relay pic 2.jpgrelay pic 3.jpg