# Just had a power cut now EmonPi won't start

**URL:** <https://community.openenergymonitor.org/t/just-had-a-power-cut-now-emonpi-wont-start/17842>\
**Category:** emonSD\
**Created:** [28 May 2021 09:52 UTC](https://community.openenergymonitor.org/t/just-had-a-power-cut-now-emonpi-wont-start/17842 "2021-05-28T09:52:56Z")\
**Posts on this page:** 1\
**Showing post:** 7

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**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\
**Post date:** [30 May 2021 11:12 UTC](https://community.openenergymonitor.org/t/just-had-a-power-cut-now-emonpi-wont-start/17842/7 "2021-05-30T11:12:32Z")

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Try reading this

> [@EmonPi purchase options - sd cards](https://community.openenergymonitor.org/t/emonpi-purchase-options-sd-cards/16240):
>
> Hi guys When ordering an emonPi, there are two options for the SD card. What’s the difference between the standard SD card and the industrial SLC one? I see another community comment that the SLC is not more reliable. Cheers!

and

> [@SD card durability: Industrial SLC NAND SD cards?](https://community.openenergymonitor.org/t/sd-card-durability-industrial-slc-nand-sd-cards/15537):
>
> We’ve put considerable effort into controlling the amount of writing the emonPi does to an SD card to prolong SD card life. The results seem to be pretty good, we’ve had SD card running for a number of years without any issues. However, there has been occasional reports of SD cards failing prematurely. Especially after power cuts. We usually use standard [Kingston SDCS2/16GB](https://docs.rs-online.com/1360/A700000006563904.pdf) micro SD cards. Frustratingly SD card datasheets don’t quote expected write limits. I’m considering doing some testing wi…

Whatever you do, **DON’T** get a card smaller than the pre-packaged image. It is possible to reduce the image from 16 GB to 8 GB (I’ve done it to use an “old” SD card for testing purposes), but it’s infinitely harder than expanding an 8 GB image to 16 GB.

Balena Etcher is the recommended way to flash the card, and if you do get a 32 GB one, expanding the 16 GB image with GParted whilst still in your laptop/card writer to use all of it is very easy and quick.

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