# Safety SLX842 with X20Cp0411 **URL:** \ **Category:** Controls & Vision\ **Tags:** integrated-safety\ **Created:** [February 26, 2025, 6:49am UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035 "2025-02-26T06:49:23Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![DragosMarin](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/dragosmarin/32/5664_2.png) [@DragosMarin](https://community.br-automation.com/u/DragosMarin)\ **Post date:** [February 26, 2025, 6:49am UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035/1 "2025-02-26T06:49:23Z")
Hello, I have in a system a X20SLX542 Safety and an X20CP0411 PLC. I did not found a hardware limit resources that excludes X20Cp0411 but I noticed that If i start the MappSafety i kill the plc (it gets in the service mode with memory violation). I tested the same software with an X20CP0484-1 PLC and The mappSafety web Page is opening without problems. As a solution I am tiring to use Safety Releases but i am struggling in getting information about how to use it. I managed to set everything and to build a small app in SafeDesigner ![SafeDesigner](https://europe1.discourse-cdn.com/brcommunity/original/2X/9/930653d3039a065608bf42d5e7c047d9fe0753e8.png) But I can not connect to the safe plc and I think the app is not yet on the SafePLC. ![image](https://europe1.discourse-cdn.com/brcommunity/original/2X/9/9aecc3755d2d2120f346da7fc8e72bb037044851.png) Please let me know If you have any ideas than can help. ---
**Author:** ![Zwi](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/zwi/32/103_2.png) [@Zwi](https://community.br-automation.com/u/Zwi)\ **Post date:** [February 26, 2025, 7:23am UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035/2 "2025-02-26T07:23:36Z")
See [this post](https://community.br-automation.com/t/troubleshooting-steps-for-connecting-to-sl-or-slx-safety-controllers/354) for trouble shooting in general. I don’t know about X20CP0411 but I’d expect some logger messages which could provide some more details… ---
**Author:** ![jan.van-de-wielle](https://avatars.discourse-cdn.com/v4/letter/j/FF8800/32.png) [@jan.van-de-wielle](https://community.br-automation.com/u/jan.van-de-wielle)\ **Post date:** [February 26, 2025, 10:18am UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035/3 "2025-02-26T10:18:16Z")
The problem with CP0411 is that it lacks RAM to operate the mappSafety webpage as it only has 128MB instead of the required 256MB: [AH || conditions to use mappSafety](https://help.br-automation.com/#/en/4/safety/mapp_safety/general/rahmenbedingungen.html) What you can try is to disable the mappSafety HMI and then use SafeDesigner to commission the application. We did this in the past with X20CP0410 and this was possible when mappSafety HMI was deactivated. Good luck! Jan ---
**Author:** ![DragosMarin](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/dragosmarin/32/5664_2.png) [@DragosMarin](https://community.br-automation.com/u/DragosMarin)\ **Post date:** [February 27, 2025, 1:02pm UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035/4 "2025-02-27T13:02:22Z")
![image](https://europe1.discourse-cdn.com/brcommunity/original/2X/c/c2d417ad123727ba9a27284aca805228893e546b.png) This is what i get when using SafetyReleases instead of mapp safety. The safety object is on plc but somehow the app i think is not. And i can not go online form safeDesigner. ---
**Author:** ![Zwi](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/zwi/32/103_2.png) [@Zwi](https://community.br-automation.com/u/Zwi)\ **Post date:** [February 27, 2025, 1:27pm UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035/5 "2025-02-27T13:27:48Z")
Looks like it is missing the application because it is not yet downloaded. Remember to use [Remote Control](https://help.br-automation.com/#/en/6/safety%2Fmapp_safety%2Fprogramming%2Fsafedesigner%2Fdlg-control%2Fremote_control%2Fremote_control.html) for that (NOT [SafePLC dialog box](https://help.br-automation.com/#/en/6/safety%2Fmapp_safety%2Fprogramming%2Fsafedesigner%2Fdlg-control%2Fkontrolldialog.html) because that won’t work until SLX is running correctly!) ---
**Author:** ![DragosMarin](https://dub1.discourse-cdn.com/brcommunity/user_avatar/community.br-automation.com/dragosmarin/32/5664_2.png) [@DragosMarin](https://community.br-automation.com/u/DragosMarin)\ **Post date:** [February 27, 2025, 2:23pm UTC](https://community.br-automation.com/t/safety-slx842-with-x20cp0411/6035/6 "2025-02-27T14:23:19Z")
Thank you! Yes, I completely forgot about Remote Control. I have the app on the plc now. So to resume: 1. To make it functional with X20CP0411 and mappSafety I had to deactivate the WebServer, and the HMI Visualisation for Safety (because 0411 has 128MB instead of the required 256MB - thank you Jan Van-De-Wielle) . 2. After this I had to use Remote Control to download the app.