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Looking for an explanation; voltage drops and fuses!
When we look for a parasitic draw we voltage drop across a fuse. A fuse is not a load as far as I understand, but a piece of metal designed to separate at a certain amperage, a piece of metal that completes a circuit so voltage can flow. My question is why can I read a voltage drop across either side of a fuse and get reading for difference in electrical potential if a fuse is not a load?
If this question is answered somewhere in the book or the video classes bear with me, I haven’t seen it all yet.
Actually every conductor IS a load as it offers resistance to the flow of current. It takes some energy to get thru and this is what causes a voltage drop. In the case of a fuse this voltage drop may be very tiny. Nevertheless it is there and the best thing is that's proportional to the actual current flow, allowing to calculate it using Ohm's law. The measured voltage drop divided by the known resistance of the fuse reveals the actual current flow.
The following user(s) said Thank You: Noah, Tyler, Chad
Blechvogel pretty much nailed it, I just wanted to add in this link that Scanner Danner posted is few weeks back in the Service Information links thread. It's a voltage drop chart for the different fuses you will find from Power Probe.
powerprobe.com/wp-content/uploads/2025/0...ltage-drop-chart.pdf
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