Burden Resistor calculation: Difference between revisions

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This will compute ICAL.
This will compute ICAL.


ICAL = Nturns / R
[[File:Ical_calculation.png]]
 


'''ICAL''': Current Coefficient<br>
'''ICAL''': Current Coefficient<br>
'''Nturns''': Number of CT sensor turns<br>
'''Nturns''': Number of CT sensor turns<br>
'''R''': Burden resistor value in Ohm<br>
'''R''': Burden resistor value in Ohm<br>

Revision as of 11:14, 10 February 2022


Burden Resistor Formulae

R: Burden resistor value in Ohm
Vadc: ADC reference voltage

This is 3.3V for all RPICT3T1 RPICT3V1 and RPICT8/RPICT7V1/RPICT4V3 in version 3 and earlier.
This is 4.096V for all RPICT8/RPICT7V1/RPICT4V3 in version 4 and 5.

Nturns: Number of CT sensor turns (see specs).

SCT-013-000 is 2000 turns.
SCT-019 is 6000 turns.
SCT-006 is 800 turns.

Nturns can be deduced dividing primary current by secondary current. For example the SCT-013-000 is rated as 100A/50mA. Therefore we get 100/0.05 = 2000 turns.
Irms: Max current to be read in Ampere (rms)

Current Coefficient Formulae

This will compute ICAL.


ICAL: Current Coefficient
Nturns: Number of CT sensor turns
R: Burden resistor value in Ohm