Burden Resistor Value.


The calculation of the burden resistor in page http://openenergymonitor.org/emon/buildingblocks/ct-sensors-interface gives a value of 33 ohm (Case Arduino running at 5V).

Question: Why is the value for the burden resistor on the EmonTxShield powered by 5V not this 33 ohm but only the half of it (because there are 2 resistors of 33 ohm in parallel)? (The EmonTx is similar.)

Thanks in advance,



Robert Wall's picture

Re: Burden Resistor Value.

There are not two resistors in parallel. There is provision for a wire-ended resistor in parallel with the SMT one should you want to easily change the value, say because you use a different ct.

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