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TheHWcave / Peacefair-PZEM-004T-

reverse-engineered schematics and interface software
MIT License
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Why replacing R17 as it works and module is calibrated for ? #7

Open Gjuju opened 6 months ago

Gjuju commented 6 months ago

As the title say, i'm confuse over the aim in changing R17 with R17a/R17b couple of resistors.

Is it just for a power dissipation reason ?

Or is there something i missed?

best regards.

TheHWcave commented 6 months ago

No, it is because of the voltage rating. The resistor has to sustain full mains voltage. The used resistor size is similar to resistors that are not rated for that kind  of voltage across them. It may arc over. By splitting the resistance value into  multiple resistors in series, each resistor has to withstand less voltage. For extra safety you may want to split into even more than just 2 resistors.  

On Monday, 13 May 2024 at 20:33:42 BST, Julien Gainza ***@***.***> wrote:

As the title say, i'm confuse over the aim in changing R17 with R17a/R17b couple of resistors.

Is it just for a power dissipation reason ?

Or is there something i missed?

best regards.

— Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you are subscribed to this thread.Message ID: @.***>