INA228: Energy Counter Polarity

Philipp Zavarsky

Part Number: INA228

Hello!
We want to use the INA228 for an energy meter for an battery powered motor application.
At our fist test we found out the the accumulated energy is always positive and the absolute value of the energy is counted.
Since we have a dynamic system with currents and therefore power and energy in both directions (in and out of the battery) this behaviour (bug or feature) is a major drawback for our application.
Why is that so?
Are there similar devices which can accumulate energy in both directions?
Why is it just a sidenote in the datasheet?

10 months ago

0 Mohamed Hamida 10 months ago

TI__Expert 6602 points

Hi Philipp,

The energy accumulator is the absolute value on all our devices. However, the charge accumulator is directional. Also, you could use the energy register combined with direction information from the shunt voltage register to keep track of positive and negative energy separately on your MCU.

Best,

Mohamed

0 Philipp Zavarsky 9 months ago in reply to Mohamed Hamida

Prodigy 10 points

This is only valid if the current direction does not change between the register readings. And the voltage stays konstant over this time. And then I still have to accumulate the values in the controller.

0 Mohamed Hamida 9 months ago in reply to Philipp Zavarsky

TI__Expert 6602 points

Hi Philipp,

I'm sorry but our devices are not designed to track power separately in both directions. Unfortunately there isn't much we can do about this, I apologize for the inconvenience.

Best,

Mohamed

0 Philipp Zavarsky 9 months ago in reply to Mohamed Hamida

Prodigy 10 points

Would be a nice feature for a new version. :-)

0 Mohamed Hamida 9 months ago in reply to Philipp Zavarsky

TI__Expert 6602 points

Agreed! I will reach out to Systems with this idea. Thank you!

Amplifiers

Amplifiers forum

INA228: Energy Counter Polarity