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Need a circuit to put between a 555 timer and a relay

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Junior Member level 1
Aug 31, 2006
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hi all,
i need a small circuit between 555 timer and a relay to avoid any problems
"i want to control the relay by a stable 555 timer"

555 relay timer

connect a diode across the relay in reverse bias under normal operation,.... this will take care of the protection.... this diode is called free wheeling diode....

ewb relay

hi all
the problem in details is when i connect the relay to the o/p pin of the 555 time "in monostable connection" normally the led lights for a certain time and be off
but In the presence of the relay it be on always
can u help me??

555 timer diode relay

Seems like you may be pulling current through the relay coil. Are you sure that the led and resistor is across the relay coil and not to another power rail. From memory the 555 will sink up to 200ma, that is to say the relay connects to the output pin and the other end to the + supply. You should connect a diode across the coil with the Cathode (band) to the + side. There is lots of 555 info on the net with circuits if you do a search. Hope this helps.

555 toggle circuit

IF the frequency ON/OFF of 555IC is larger then 24HZ , you can't see led on/off so you can't test the circuit by that way!
Try to hear the sound of relay when Relay stick is on/off sate.

best way to connect relay with 555 timer

if it was in operation when connected directly then it would be working when connected using relay too... i think current is passing even when the relay is supposed to be off.... please post your circuit and give us a clear insight....

astable 555 timer with relay

the file opens by EWB "electronic work bensh"

picture 555 timer

Please printscreen the circuit and post it.... then it would be easier...

connecting a 555 timer to a relay


**broken link removed**

relay toggle circuit using 555 timer

in the figure you have posted the LED glows because the transistor Vbe drop when it is on has to be satisfied by the other path too and the other path contains the LED and hence it glows.... the relay doesn't have these restrictions so please tell how you connected the relay.... a picture with the relay usage would be helpful.... please post it....

connect relay to 555 timer

i can't understand what u need??
the picture i sent it has all connections including the relay connection.........
the problem now in this picture is when the 555 trigered ,the o/p of it is 5V always

timer relay

i dont understand how your output can be 5V always because a 1kΩ resistor and the base emitter junction are in series in between the output pin and the ground and since the base current of the transistor will be in µAs the voltage across it be around 2V at the maximum else the transistor will be burnt out.... measure the base current of the transistor and post it please....

relay toggle circuit using astable 555 timer

Have a look at:

**broken link removed**

There is a Relay Toggle Circuit Using a 555 Timer.

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