Signal to WHAT? Voltage level only or turn on a current pulling load? Not enough infoQuote:
Originally Posted by eastvolt
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Signal to WHAT? Voltage level only or turn on a current pulling load? Not enough infoQuote:
Originally Posted by eastvolt
its for a hidden key fob starter. key fob device is supposed to send 5v+ signal when keyfob is next to sensor. Unfortunately its only givin out 3.54v not enough to activate the coil. The relay is supposed to switch on 12v+ to a 50amp 12v relay to crank the starter.
I was finally able to find a relay with a 3v coil and i think i is rated at 10amp. A little pricey but it should work. Ill let you know how i goes when it comes in the mail. Thanks for all your guys help.
I would try one of these solid state relays:
Crydom DMO063 -- RELAY SSR 3A 60VDC SPST-NO SIP
available from Digikey for $17.52
http://search.digikey.com/scripts/Dk...name=CC1139-ND
This is what i got hopefully i will receive them early next week
http://cgi.ebay.com/ws/eBayISAPI.dll...m=180185400188
okay i cant take it anymore!!!! i guess i will move on with my post count ;)
Simple fix might be to add a transistor and a resistor to the mix to trigger the relay with 3.54 Volts. May even be able to trigger around 2.6Volts which is from what i remember the switching voltage of a 2n2222. i could be off by a little. Anyways, here is a picture to help. I used PAINT :)
3 volts to 220 ohms should be okay to trigger the transistor at its base, which will allow voltage to pass through it to ground. Then the relay coil can be connected to what ever voltage can trigger it like 5volts or 12volts etc. You may want a resistor between the relay coil and power to lower current draw from the relay. Only if you plan on using a 7805 to regulate 5volts to trigger the relay.
Feels good to be back....... :bathbaby:
Personally I would have just used a transistor to increase the current drive capability of the key fob detector. It sounds like it does put out 5v, but drops under the loads required to drive the relay.
Edit : pRoFiT and I came to the same conclusion at the same time.
yes but i painted a picture ;)Quote:
Originally Posted by Rob Withey
Well done. I couldn't be bothered, not for such a simple problem.Quote:
Originally Posted by pRoFiT
Thanks for pitching in and helping with suggestions guys. I agree that a circuit is a better solution but I don't know if the OP can deal with it. That transistor driver needs for there to be a protection diode clamper across the relay coil or it will probably only turn on and off one time. I suspect that a 3V electromechanical relay will not work any better than the 5V one did without some extra help.