I built the circuit below, and added an extra relay with 12 volts at 87A and nothing at 87. I used the output from 30 on the first relay to control the added relay, basically making the circuit normally closed. My question is, can the circuit be modified to do this without adding a relay?
how much current do you plan to draw from this. if its less than 15-20 amps...
late 60s and early 70s VW bugs used a relay that was a mechanical latching design that only consumed power while flipping from one output to the other.
it was for dimming the headlights back and forth from dim to bright etc.... it is one of the coolest designs you will ever see. a DEI relay driver can NOT be used alone to ground/flip the relay... but most switches have no problem at all. it pulls about 1-2 amps to flip it.
i use them for fuel pump kills on my own anti carjack circuits. there are so many uses for them. they are about 25-30 bucks used on ebay and last for decades.
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yuk
quiet rural missouri, near KC.
If your system moves you physically and not emotionally, you have wasted your money.
I could probably find a ton of uses for those. My circuit is protected by a 10 a fuse.
yep..
they have 4 terminals and the housing does not need to be grounded for the unit to operate.
on a VW, one terminal gets powered when the headlight switch is turned on.
power flows two places from that terminal.
1. to to and articulating set of contacts to which ever bulb terminal was used last (dim or bright).
2. to the relay coil.
then when the turn signal lever is pulled back it causes the 4th terminal to get grounded for a moment it completing the current through the coil causing the power to get flipped to the other bulb terminal.
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yuk
quiet rural missouri, near KC.
If your system moves you physically and not emotionally, you have wasted your money.
Thanks for the info.
I would still like to solve the riddle above though. It's pretty simple I'm sure, just a little hard to follow the diagram through the on an off conditions of each relay. I tried swapping the wires on 87 and 87a on the first relay. When that didn't work out I studied the diagram a little more and it became obvious why it wouldn't work, but I still haven't figured out how to do it.
my first concern is battery drain from relays being energized when the key is off.
thats why i was wanting to know the intended application of the whole thing.
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yuk
quiet rural missouri, near KC.
If your system moves you physically and not emotionally, you have wasted your money.
It's not a problem. It's on a key on only circuit. Just running an accessory with a momentary switch. Less than 10A. I already have it working perfectly by adding a 6th relay to the circuit. I just want to figure out how to wire it so I don't need the extra relay.