# EM7455 Power-Off Sequence **URL:** \ **Category:** IoT Modules\ **Created:** [June 25, 2020, 12:36pm UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746 "2020-06-25T12:36:41Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![timclacy](https://avatars.discourse-cdn.com/v4/letter/t/48db29/32.png) [@timclacy](https://forum.sierrawireless.com/u/timclacy)\ **Post date:** [June 25, 2020, 12:36pm UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/1 "2020-06-25T12:36:41Z")
According to the AirPrime EM7455 Specification, there is a recommended power-off sequence to mitigate against on-board file-system corruption. This sequence can take up to 25 seconds. ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/7/7a2f4c4ed6b4695e2f99a94ed3ccff7b3757a502.png) **QUESTION:** If the EM7455 is first made ‘safe to remove’, can the power be cut immediately after? On Windows, there is a ‘safely remove’ feature, which can be done programmatically using the ’ CM\_Request\_Device\_Eject’ API. Does this permit immediate removal of power? ![image](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/7/7e5e63876c7d91bb4981f675ab23f631faedc687.png) ---
**Author:** ![Vianney](https://avatars.discourse-cdn.com/v4/letter/v/71e660/32.png) [@Vianney](https://forum.sierrawireless.com/u/Vianney)\ **Post date:** [June 26, 2020, 8:49am UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/2 "2020-06-26T08:49:42Z")
Hi @timclacy, Safely remove support to eject device from PC without powering off the module. I tried on Window 10, EM7455 is immediately removed from PC. ![Screenshot_5](https://us1.discourse-cdn.com/flex025/uploads/sierrawireless/original/2X/2/22ca30bc379f1cc5c9b9a2c6e93bd218d02f8e7c.png) Please share any concerns you have and help us tick **Solution** if your question is answered Thanks ---
**Author:** ![timclacy](https://avatars.discourse-cdn.com/v4/letter/t/48db29/32.png) [@timclacy](https://forum.sierrawireless.com/u/timclacy)\ **Post date:** [June 26, 2020, 9:17am UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/3 "2020-06-26T09:17:26Z")
Hi Vianney, Yes. But my question was regarding the power-off sequence in the EM7455 datasheet. I wanted confirmation that we can ignore the power-off sequence if we first do ‘safely remove’ hardware. In other words, can you confirm that we can cut power immediately after doing ‘safely remove’ without any risk of corruption to the module’s internal file-system. I suspect it is safe to cut power immediately after ‘safely remove’, which means that the datasheet is a bit misleading. Cheers Tim ---
**Author:** ![Vianney](https://avatars.discourse-cdn.com/v4/letter/v/71e660/32.png) [@Vianney](https://forum.sierrawireless.com/u/Vianney)\ **Post date:** [June 26, 2020, 10:06am UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/4 "2020-06-26T10:06:57Z")
Hi @timclacy, As I said safely remove is a feature of Window which supports to remove connection between your PC and the module, it doesn’t cut power of the module. It will be turned off only if you unplug the cable from the module. We don’t recommend customer do this because it will cause the unexpected errors afterward. Thanks ---
**Author:** ![timclacy](https://avatars.discourse-cdn.com/v4/letter/t/48db29/32.png) [@timclacy](https://forum.sierrawireless.com/u/timclacy)\ **Post date:** [June 26, 2020, 10:21am UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/5 "2020-06-26T10:21:45Z")
Thanks for answering but now you’re saying that you don’t recommend customers unplug the module from USB or it could cause unexpected errors. In other words, you are saying that after doing ‘safely remove’hardware’ it’s still not safe to remove the hardware. Is that correct? Thanks ---
**Author:** ![mlw](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/mlw/32/3706_2.png) [@mlw](https://forum.sierrawireless.com/u/mlw)\ **Post date:** [June 29, 2020, 12:57pm UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/6 "2020-06-29T12:57:11Z")
@timclacy The short answer to your question is unfortunately no. The 25 seconds is an extreme to cover every eventuality, we have put as many safe guards in as possible to guard against corruption but there remain some we just cannot completely mitigate. Regards Matt ---
**Author:** ![timclacy](https://avatars.discourse-cdn.com/v4/letter/t/48db29/32.png) [@timclacy](https://forum.sierrawireless.com/u/timclacy)\ **Post date:** [June 29, 2020, 1:10pm UTC](https://forum.sierrawireless.com/t/em7455-power-off-sequence/20746/7 "2020-06-29T13:10:24Z")
Thanks for the reply.