> For the complete documentation index, see [llms.txt](https://docs.enlyze.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enlyze.com/en/connect/ot-connectivity/supported-controller-brands/siemens.md). # Siemens Siemens is the leading provider of automation technology in Europe, so Siemens devices are the controllers we encounter most often. The controllers have been sold under the **SIMATIC** name since the 1980s. This has grown into a broad product landscape, ranging from small logic modules (LOGO!) and compact or modular PLCs to large, highly available systems. ENLYZE connects Siemens controllers via two native protocols over Ethernet. Both run over RFC1006 (ISO-on-TCP, default port `102`): * **S7+** (S7CommPlus): the native and more performant protocol of the TIA Portal generation (S7-1200, S7-1500, and variants). It is required to access optimized data blocks and is the recommended connection for these devices. Connections are made through the [S7+](/en/connect/ot-connectivity/supported-industrial-protocols/s7+.md) connector. * **S7 Classic** (S7comm over RFC1006): the classic S7 protocol of the S7-300 and S7-400 generations. It addresses data through absolute addresses (e.g. `DB1.DBW0`). As a vendor-neutral alternative, many Siemens controllers also offer an OPC UA server. It can be enabled on the S7-1500 and on the S7-1200 (from firmware V4.4) and must be licensed on the controller. {% hint style="warning" %} **OPC UA server on S7-1200 / S7-1500: limited performance** The integrated OPC UA server runs on the controller's CPU itself. This limits the number of variables you can read simultaneously and the minimum sampling interval, and it puts additional CPU load on the controller. For most S7-1500 CPUs, Siemens recommends a maximum of around 4,000 monitored items at a minimum sampling interval of 100 ms, and only under the assumption of at most 50% communication load (see [OPC UA system limits](https://support.industry.siemens.com/cs/ww/en/view/109755846), Siemens Industry Online Support). In comparison benchmarks, the native S7 connection reads far more datapoints at lower CPU load than the OPC UA server, around 2,600 datapoints in roughly 200 ms at about 5% additional CPU load, while the OPC UA server already hits its limit at around 300 variables every two seconds ([benchmark: S7 driver vs. OPC UA](https://industrialmonitordirect.com/blogs/knowledgebase/ignition-s7-driver-vs-opc-ua-tag-limit-performance)). For the S7-1200 and S7-1500 we therefore recommend the native **S7+** protocol. It reads out more variables and puts less load on the controller. {% endhint %} {% hint style="info" %} The manufacturer alone is not decisive, but rather the specific device and the available interface. Controllers without an integrated Ethernet interface (such as older, serial-only S7-200 or PROFIBUS-only S7-300 CPUs) can only be connected if they are extended with a corresponding network module (CP). {% endhint %} {% hint style="info" %} **S7-300 / S7-400 without an Ethernet interface** If an S7-300 or S7-400 only has a PROFIBUS or MPI interface, we use a **PROFIBUS/MPI-to-Ethernet adapter for connecting S7 controllers**. It bridges the controller's serial interface to the Edge Device, so the connection can then be made through the S7 Classic connector. {% endhint %} {% hint style="info" %} **Automatic variable detection** The S7+ protocol supports [Variable Discovery](/en/connect/ot-connectivity.md#variable-discovery). The controller's variables are therefore detected automatically. Unlike purely address-based protocols, the memory addresses do not need to be known in advance. If the controller is password-protected, the password is required for access. {% endhint %} ## Device overview The following table gives an overview of the Siemens families and typical devices. The **Generation** column distinguishes the classic generation (programmed with STEP 7 Classic / SIMATIC Manager) from the TIA Portal generation and determines which protocol is used. The **Recommended connector** column names the connector with the best data throughput and highest stability for each family. The **Status** column indicates whether we have already connected the family in the field. | Series | Typical devices | Generation | Recommended connector | Status | | --------------- | --------------------------------------------------------------------------------------------------------------------- | ------------------ | ------------------------------------------------------------------------ | ---------------------------------------- | | S7-1500 | CPU 1511, 1513, 1515, 1516, 1517, 1518 (incl. F / T variants), R/H (redundant), Drive Controller, Software Controller | TIA Portal | [S7+](/en/connect/ot-connectivity/supported-industrial-protocols/s7+.md) | ✅ Supported | | ET 200SP (CPU) | CPU 1510SP, 1512SP, 1515SP PC (Open Controller) | TIA Portal | [S7+](/en/connect/ot-connectivity/supported-industrial-protocols/s7+.md) | ✅ Supported | | S7-1200 | CPU 1211C, 1212C, 1214C, 1215C, 1217C | TIA Portal | [S7+](/en/connect/ot-connectivity/supported-industrial-protocols/s7+.md) | ✅ Supported | | S7-300 | CPU 312, 314, 315-2 PN/DP, 317-2 PN/DP, 319-3 PN/DP, 31xC (compact) | Classic | S7 Classic (RFC1006) | ✅ Supported | | S7-400 | CPU 412, 414, 416, 417 (incl. H variants for redundancy) | Classic | S7 Classic (RFC1006) | ✅ Supported | | S7-200 SMART | SR20, SR30, SR40, SR60, ST20, ST30, ST40, ST60 | Micro/WIN SMART | S7 Classic (RFC1006) | 🧪 Likely possible, not yet field-tested | | S7-200 (legacy) | CPU 221, 222, 224, 224XP, 226 | Legacy | serial, Ethernet only via CP243-1 | 🧪 Likely possible, not yet field-tested | | S5 | S5-90U, S5-95U, S5-100U, S5-115U, S5-135U, S5-155U | Legacy (STEP 5) | S5 (SINEC H1, passive) | ✅ Supported | | C7 | C7-621, C7-633, C7-635, C7-636 (HMI + S7-300 CPU) | Classic | S7 Classic (RFC1006) | 🧪 Likely possible, not yet field-tested | | LOGO! 8 | LOGO! 8 (0BA8) with Ethernet interface | LOGO! Soft Comfort | Modbus TCP | ✅ Supported | {% hint style="info" %} **SIMATIC S5** The SIMATIC S5 is Siemens' controller generation before the S7 (programmed with STEP 5). ENLYZE connects it via the **SINEC H1** protocol. The connection is passive: the Edge Device listens to the network traffic between the controller and its communication partner and reads the values from the memory areas (DB, MB, EB, AB). This requires the S5 to generate SINEC H1 traffic through a communication processor (e.g. CP 1430) that the Edge Device can receive. Connecting an S5 requires additional hardware in the form of an adapter, which comes with further limitations. In these cases an on-site visit is therefore always required. {% endhint %} {% hint style="success" %} **Rule of thumb:** connect TIA Portal generation controllers (S7-1200, S7-1500, and their variants) via **S7+**, and classic controllers (S7-300, S7-400) via **S7 Classic**. If an OPC UA server is licensed on the controller, **OPC UA** is the vendor-neutral alternative, but for the S7-1200 and S7-1500 the native S7+ is more performant. {% endhint %} {% hint style="warning" %} The families **S7-200 SMART**, **S7-200**, and **C7**, as well as the S7-1500 variants R/H, Drive Controller, and Software Controller, are technically connectable but have in some cases not yet been connected by us in the field. If you want to connect such a device, feel free to contact us at so we can check the connection together. {% endhint %} {% hint style="info" %} The controllers from [Yaskawa (VIPA)](/en/connect/ot-connectivity/supported-controller-brands/yaskawa.md) are largely compatible with the Siemens S7-300 and are connected through the same S7 Classic connector. {% endhint %} If you have any questions, feel free to contact us at . --- # Agent Instructions This documentation is published with GitBook. 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