are fuses always on 12V side of a device?

I find a lot of vehicles used "switched earth" system, where devices join
to a 12 V main wire, and are switched on the earth side. But then, would
the fuse still be on the hot side for extra safety?
So I believe it should look like this:
12V--fuse--lamp--switch--earth
Reply to
pedro1492
Never seen a fuse on the ground side in anything I've worked on. You fuse the hot side to protect the entire circuit. A fuse on the ground side would do nothing if the problem is prior to the fuse.
12V--load--switch--fuse--earth
Everything from the 12V feed to the fuse is actually unprotected.
Reply to
Steve W.
wrote:
Yes. If there is a short to earth anywhere along that path, the fuse blows. If the fuse were on the earth side, that would not be the case.
You will occasionally see fuses on both sides of the line on systems that may have multiple paths to ground, like two-way radios. The ground fuse will blow if the two ground points have appreciably different voltages and substantial current flows between them. --scott
Reply to
Scott Dorsey

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