On 12/2/20 2:47 AM, Johann Klammer wrote:
On 12/02/2020 03:41 AM, Jezebels_couz wrote:
In the process of finishing a 0-12 VDC @ 0-10 A switching power supply. Fairly new at this and wanted to ask about the shunt resistor. It will be in the ground line. Plans mentioned two options: either a custom shunt made from constantan wire or similar, or simply two 5W 0.1 ohm power resistors in parallel. Since I wanted to keep costs down, I am going with the power resistors, but I have a concern: I will be running 12 gauge wire for the output lines, but when the ground wire reaches the shunt, even the two resistors in parallel combined are far less than 12 gauge. Should I be concerned, or is the tiny resistor/ 12 gauge wire distance (basically just for the 12 ga wire to resistor wire connection) irrelevant to heating and losses?
If it's not too long, the heat might dissipate through the adjoining traces.
(if they didn't lie about the resistor wattage, that is)


Here's a diagram of what I was trying to explain. I wasn't sure I was
very clear, so hopefully the diagram will better relate:

https://i.imgur.com/pYSRxiX.jpg