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Transition Zone Transition Zone is offline
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Default shunt/ current sense resistor question

On Wednesday, December 2, 2020 at 2:57:16 PM UTC-5, Jezebels_couz wrote:
On 12/2/20 2:47 PM, Ralph Mowery wrote:
In article , says...


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



I understand what you are going to do.

To put your mind at ease Astron that makes power supplies has a 20 amp
one that has two pass transistors. That means that each one would be
good for 10 amps. They use only one .1 ohm 10 watt per transistor.

I have larger ones that do the same thing and they have worked for years
with no problems.

Each of your resistors will need to be less than 3 watts at a 10 amp
current if a quick calculation is correct.

Ok, just wanted to be sure as high current would still have to squeeze
through those small areas and I wanted to minimize heating and loss. In
my mind, it sort of defeated the purpose of using 12 gauge wire
everywhere else to have a bottleneck at the end, but if all is well then
no longer concerned. There will be two 5W resistors in parallel, so
good to go on wattage. Thanks again.


Also, most current-sensing transformers don't need that high voltage (of shunt resistors) and can isolate any especially sensitive circuitry that might be there.