# Auto calibration with ADE9153A mSure **URL:** \ **Category:** Hardware\ **Created:** [31 October 2021 00:55 UTC](https://community.openenergymonitor.org/t/auto-calibration-with-ade9153a-msure/18924 "2021-10-31T00:55:54Z")\ **Posts on this page:** 1\ **Showing post:** 6
**Author:** ![dBC](https://community.openenergymonitor.org/letter_avatar_proxy/v4/letter/d/5f9b8f/32.png) [@dBC](https://community.openenergymonitor.org/u/dBC)\ **Post date:** [1 November 2021 22:22 UTC](https://community.openenergymonitor.org/t/auto-calibration-with-ade9153a-msure/18924/6 "2021-11-01T22:22:00Z")
> [@Robert.Wall](#): > > the principal reason for OEM not using an energy measurement i.c. in their designs. Energy ICs don’t have to sit directly on one of the supply rails - in this case I think that’s more a function of them using a shunt. If you stick with CTs for measuring I (especially 333mV CTs that effectively come pre-calibrated from the factory) and a precision divider for V, you can get some pretty spectacular accuracy even without mSure. There are [techniques](https://community.openenergymonitor.org/t/zmpt101b-powerfactor-and-current-shown/11939/61) for ensuring there’s plenty of R between the IC and either of the supply rails. I should have added, in case anyone is thinking of replicating that, that’s in addition to isolation, not instead of isolation. --- _[View the full topic](https://community.openenergymonitor.org/t/auto-calibration-with-ade9153a-msure/18924)._