# Siemens S7 plc connection status

**URL:** <https://discourse.nodered.org/t/siemens-s7-plc-connection-status/97033>\
**Category:** General\
**Created:** [12 May 2025 14:50 UTC](https://discourse.nodered.org/t/siemens-s7-plc-connection-status/97033 "2025-05-12T14:50:46Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![TROJAN053](https://avatars.discourse-cdn.com/v4/letter/t/7cd45c/32.png) [@TROJAN053](https://discourse.nodered.org/u/TROJAN053)\
**Post date:** [12 May 2025 14:50 UTC](https://discourse.nodered.org/t/siemens-s7-plc-connection-status/97033/1 "2025-05-12T14:50:46Z")

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Hi,  
I want to capture the Siemens S7 PLC connection status in case of connection failure and generate some message in case of failure. I have tried using the status node but that not worked. Please help.

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**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [12 May 2025 15:12 UTC](https://discourse.nodered.org/t/siemens-s7-plc-connection-status/97033/2 "2025-05-12T15:12:25Z")

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If a node has a status dot/text underneath it, you can use the `status` node to listen for changes. Use a debug node set to show full msg to see what the status node outputs.

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**Author:** ![aitor](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/aitor/32/97363_2.png) [@aitor](https://discourse.nodered.org/u/aitor)\
**Post date:** [13 May 2025 15:27 UTC](https://discourse.nodered.org/t/siemens-s7-plc-connection-status/97033/3 "2025-05-13T15:27:21Z")

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A simple and effective way to monitor PLC connection is using a “heartbeat” flip-flop. It lets the PLC know Node-RED is online (you can trigger an alarm if not), and Node-RED can detect if the PLC goes offline—so you can log downtime, send alerts, etc.

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [11 August 2025 15:27 UTC](https://discourse.nodered.org/t/siemens-s7-plc-connection-status/97033/4 "2025-08-11T15:27:55Z")

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