how can i connect these two devices ?

[jaloud]

I designed " 555 timer " circuit .

I want connected 555 circuit with other device that acts at 220 V

for example lamp acts at 220 v and 100 w I want operation lamp for 1 hour

how can I connect two circuits ( timer and lamp ) ??


Thanks in advance

 

[keith1200rs]

A relay is probably the easiest and safest.

Keith

 

[rameeola]

i'm agree with the top comment...but if in the high freq i think it bad if use relay..

 

[keith1200rs]

True, but I think 1 hour was mentioned so I think a relay is fine!

Keith

 

[jaloud]

Thanks Keith

and

i'm agree with the top comment...but if in the high freq i think it bad if use relay..

what do you mean ?? ,, what is problem ?? at high freq.

if I choose the time of 555 ciruit 1 min , does relay work fine ?

 

[keith1200rs]

You will be fine with a relay. Relays take a few milliseconds to operate and have lifetimes from maybe 100,000 operations to 10 million so you need to bear that in mind but for your application it will be fine. You might want to add something like this to drive the relay:

The 555 may drive the relay without an extra transistor - it depends on the relay current. The diode protects the transistor from the reverse voltage from the relay when it switches off.

Sorry for the brevity of my replies earlier - I was on my mobile phone so couldn't draw circuits!

Keith.

 

[sudheepsrc]

best solution is relay

 

[jaloud]

Thanks all

Sorry for the brevity of my replies earlier - I was on my mobile phone so couldn't draw circuits!

no problem , your circuit is clear . I get your idea and I think , it is good because the O/P of 555 is 9 v .

 

[squallfxx]

Yes, realy is a good choice.

I was also thinking about a optocoupler with a diac and/or a triac..

With the relay you will always listen the coil which may become boring..