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yog1389
04-09-2007, 09:34 PM
having done my share of programming for many years i have just started trying circuits.

as my second circuit i am trying to make a cooler safety circuit that will control the on off duration of the pump, thereby enhancing cooling effect, saving electricity and water.
obviously i have copied the circuit from a book but the problem is that the circuit uses a 10 volt 300ohm rely that toggles the off-time between 4mins and 8 mins.
i live in indore(M.P.) and i cannot find 10 volt relay in the market, though 6V and 12 V are readily available.
i m using a 9-0-9 V tranformer.

what should i do ??? which relay to use and what changes should be be made to accomodate that ???

also i m using IN4007 instead of IN4001 and IN4002 diodes as they r not available. is that ok ???

docel
04-10-2007, 01:17 AM
The Relay specs does not matter, unless it is dictated by the Relay drive circuit!!!
Many 5V or even 12V miniature relays are available in India, which operate at 20 to 30 ma...and quite fast switching rate too!

Just find the Smallest PCB mount relays and it will do the job, without any change in operating/ Switching parameters.

addy
04-10-2007, 06:52 PM
relay specs is none of the concerns.
just make sure tat the relay has currennt specifications in accordance to wat current yu re trying to drive thru it..... i. e the maimum current it allows to pass thru must be greater than wat yu re trying to pass..
remaining switching action yu can do using a darlignton driver like ULN..

docel
04-10-2007, 10:41 PM
Addy!
What are you trying to say???? :evil:

just make sure tat the relay has currennt specifications in accordance to wat current yu re trying to drive thru it..... i. e the maimum current it allows to pass thru must be greater than wat yu re trying to pass..
Dont confuse the already confused guys, technically.....(thats beside your ENGLISH, and it is completely incomprehensible) :!:

addy
04-11-2007, 03:34 PM
alright...
i was saying that if the relay can bear only, say 1amps of current, and if he tries to drive a device consuming 5 amps of current, he is simply risking the relay.
tats all....

Dont confuse the already confused guys, technically.....(thats beside your ENGLISH, and it is completely incomprehensible)
its not completely incomprehendible... guess i should ve written it in a more simpler way.
but why re we breaking our heads into it, the guy who askd for it has anyway not responded... :lol:

yog1389
04-21-2007, 08:50 PM
thanks ; both of you. sorry for late reply guys. i m not getting confused. actually the relay current specs did not match that of which i needed. (min current was less than base collector current). i did not used a darlington driver. instead i put a high resistance in parallel (basic physics) to reduce the current.


thanks anyways.
thanks a lot.