Was thinking of putting one of these to drop 12 to 6 volts for the fuel gauge on me split, it says the input earth can come from the body but the output earth goes to the item, trouble is the gauge is earthed to the body, would `I just earth the output to the body then??? http://www.ebay.co.uk/itm/12V-to-3-...hash=item283e2b76ec:m:mSHzUhJt2s4nab-bp35IZ-g
I can't see any reason (giving it minimal thought ) why you shouldn't effectively connect the input and output grounds together. Who says the bit about "output earth goes to item"? However...not quite sure what you're trying to do. Is your splitty a 12V system? Is the fuel gauge a "6V" one? Does it have a voltage regulator already for the fuel gauge?
Says its a buck regulator . So the earth is a common earth, the input and output share the earth as that is how these regulators work. In goes 12 volts from somewhere ignition switched and out comes exactly 6 volts. That would feed the gauge positive and the gauge would feed the wire to the sender which then creates the circuit to ground for the current flowing from the 6 volt output. Assuming your gauge needs 6 volts regulated.
If you have the item get a multimeter and confirm the black and yellow wires are continuous (0 Ohms) if so you are good to go
If it said Isolated converter then the grounds would be separated and you would have to connect both. And the description would babble on about isolation voltages which it does not. So black and yellow will be connected inside the module. If they are not then it is crazy junk.
Its just a ground to the sender and the gauge senses the resistance 8 ohms full 80 ohms empty I think your right with the earth though as they are all connected really, Thanks
