when connecting my car system is it better to earth direct from battery?
- cato___Lv 71 decade agoFavorite Answer
When connecting your car system? Didn't your car system come connected to the car battery?
In any event, it is pretty much always better to make electrical connections as directly as possible, so, yes is most likely the answer to your question.
If you connect what ever it is you are talking about indirectly, through the car frame or on some shared ground wire, then your system will be more vulnerable to picking up noise from the other equipment and from breaks due to rust etc...
- NomaddLv 71 decade ago
With any high current system it's better to hook the negative directly to the battery. When you draw a lot of current through a common ground wire you create a bit of a voltage drop on that wire and your gauges and lights will tend to fluctuate.
- Anonymous1 decade ago
If you are talking about a radio, NO. Hook it to any bare metal surface. The entire frame and metal structure of the car is grounded (earthed (wtf)) to the battery.