hie every one i have made an rc car but am having some problems with the relays used in it they consume most of the power of my car is there any alternatives to the relays ????????? i cant use the h bridge configuration i need some thing like a relay but which consumes less power plz help i have to submit it as soon as possible
plz help

 

Can you post a circuit diagram? Why can't you use MOSFET's etc.?

 

Typically, relays are very power-hungry, as the coils need to be energized to close the N.O. contacts. It's easy to create an electromechanical H-bridge with a couple of SPDT relays. If you want something more efficient, you will have to go with an H-bridge configuration.

Check out Steve Bolts' 4-transistor H-bridge on BEAM circuits:
http://www.solarbotics.net/library/circuits/driver_4varHbridge.html
Needs a Vcc of 4.5v to 6v, uses 2 inverters from a 74HC14 IC.

 

here is the pdf version if the circuit and the part list
i have not uploaded the relay configuration but plz try to figure out something i am just a bigner need help as soon as possible
thx in advance hope you will help

if you find some thing help full then try to explain me in detail i am very dum in electronic
plz a request

 

i forgot to tell that i am using four 12v 250 rpm geared motors
and here is the relay configuration and some other pic

 

i at least got it working but it sticks a little bit when i put it in the momentary mode such as when i change the directions the relay turn on n off rapidly for few seconds and then work fine
plz help

 

You probably do not have large enough capacitors on the board that is controlling the relays.

 

You probably do not have large enough capacitors on the board that is controlling the relays.

sry sir but i didnt get you
means do i need more capacitors or are there any capacitors
and if i need so then which type of capacitors and of what value ?????????

 

sry sir but i didn't get you
means do i need more capacitors or are there any capacitors
and if i need so then which type of capacitors and of what value ?????????

See, while connecting a good load just like your DC motor you should use big capacitors like 4,000uf above 40V.
there is no dump rule to calculate it value, use any if you don't have such capacitor try to fix them in //.

 

You are using a Ready made wirelesss switch....try to use HT 12E/D for that with Rx and Tx 433,etc Mhz.