# S7-300 Connection to Ignition

**URL:** <https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982>\
**Category:** Ignition\
**Created:** [August 20, 2025, 11:25am UTC](https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982 "2025-08-20T11:25:23Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![aleksander.dovnik](https://avatars.discourse-cdn.com/v4/letter/a/7993a0/32.png) [@aleksander.dovnik](https://forum.inductiveautomation.com/u/aleksander.dovnik)\
**Post date:** [August 20, 2025, 11:25am UTC](https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982/1 "2025-08-20T11:25:23Z")

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I have an S7 315-2 PN/DP with aditional CP343-1 Lean. I am trying to connect the plc to ignition with s7-300 driver over the lean cp card.

So the problem i have is when i connect ignition i cant get online with a PG, and when i am online with PG icant connect with ignition.

The connection resurces on the PLC are set to 5-OP 5-PG 2-S7 BASIC . I tried modifing these ressureces but still no luck. Any ideas ? Maybe a problem because of the cp lean card ?

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**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\
**Post date:** [August 20, 2025, 12:59pm UTC](https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982/2 "2025-08-20T12:59:51Z")

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How many of the connection resources are in use already?  
Normally you can check this with a web browser on a 300 series unit.

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<div class="post-metadata">

**Author:** ![aleksander.dovnik](https://avatars.discourse-cdn.com/v4/letter/a/7993a0/32.png) [@aleksander.dovnik](https://forum.inductiveautomation.com/u/aleksander.dovnik)\
**Post date:** [August 21, 2025, 5:18am UTC](https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982/3 "2025-08-21T05:18:43Z")

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So to update the situation. The CP343-1 Lean apparently supports only up to 5 connections. I had more on that cp lean and thats why it did not connect

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**Author:** ![Dan\_Mor](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Dan\_Mor](https://forum.inductiveautomation.com/u/Dan_Mor)\
**Post date:** [October 1, 2025, 4:14pm UTC](https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982/4 "2025-10-01T16:14:03Z")

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How did you remove the connections to connect the ignition one?

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<div class="post-metadata">

**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\
**Post date:** [October 1, 2025, 8:16pm UTC](https://forum.inductiveautomation.com/t/s7-300-connection-to-ignition/109982/5 "2025-10-01T20:16:51Z")

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You have to remove one system that is connected.  
Connections are used by PLCs that are communicating to it over the network, HMIs and SCADA as well as any piece of software or hardware that pulls tags out of the PLC. The Step7 software also uses a connection.