Ruineng micro electric energy metering chips rn8208g, rn8209d, rn8209g, rn8209c, rn8302, rn8302b
Rn7302 and SOC rn8211, rn8211b, rn8213 and rn8215 all have an important parameter: dynamic range. For example, it is described in the user manual of rn8209c / rn8209d:
"The active power error is < 0.1% within the dynamic range of 8000:1, meeting the requirements of iec62053-22:2003 standard"
What is dynamic range?
Dynamic range: refers to the ratio of the minimum value of ADC input signal to the maximum value of ADC input signal (i.e. full-scale value) when the power metering chip guarantees specific measurement or metering accuracy (full-scale value: minimum input signal).
Take rn8209c / D as an example to explain:
Maximum value of input signal: 1000mV peak value
Dynamic range: 8000:1
Active power accuracy: 0.1%
Then, the minimum value of the input signal = peak value / 8000 = 1000mV / 8000 = 0.125 MV (effective value is 0.088mv). In the design, as long as the peak value range of the input signal is within [0.125mv ~ 1000mV] (effective value range of the input signal is within [0.088mv ~ 707mv]), the sharp energy micro electric energy metering chip can guarantee the active power accuracy of 0.1%.
Note: the above range is based on the gain multiple of ADC = 1. If the ADC multiple is not equal to 1, the range should be divided by the gain multiple.
If the current gain multiple of channel a = 16, its dynamic range 8000:1 corresponds to the range of input signal: [0.0055mv ~ 44.2mv]