Siemens LOGO! 9: what it is and the main changes
Siemens LOGO! 9 is the new generation of logic relays (micro-PLCs) for simple automation, presented by Siemens in April 2026 at the Light + Building fair. It is the first major update to the range in 11 years, since LOGO! 8. The most noticeable changes: twice the memory — 800 function blocks instead of 400, floating-point math instead of integer, a colour touch display and a built-in web editor. In plain terms, LOGO! is still as easy to set up as before, but its capability now sits close to the entry-level S7 PLCs.
What is it built for? The same jobs as always: lighting and ventilation in buildings, pump stations, gates, barriers, simple machines and test rigs. The difference is that one controller now holds logic that used to hit the 400-block ceiling. LOGO! 9 is already on sale on our site — below we go through the specs, the new modules, and whether moving from LOGO! 8 makes sense.
LOGO! 9 technical specifications
In short, LOGO! 9 doubles almost every core limit of LOGO! 8 and adds what bigger projects were missing — fractional math, a colour screen and full networking. Here is how it reads in numbers next to its predecessor.
| Parameter | LOGO! 8 | LOGO! 9 |
|---|---|---|
| Function blocks | 400 | 800 |
| Math | 32-bit integer | 32-bit floating point (float) |
| Local digital inputs (DI) | 24 | 64 |
| Local digital outputs (DQ) | 20 | 60 |
| Local analog inputs (AI) | 8 | 16 |
| Local analog outputs (AQ) | 8 | 16 |
| Network I/O | limited | NI 512 / NQ 480 / NAI 128 / NAQ 128 |
| Base module display | monochrome | colour touch 320×240 |
| Power supply | 12/24 V DC or 115/230 V AC | 12/24 V DC or 115/230 V AC |
Logic and memory
800 function blocks is the headline number of this release. On LOGO! 8 a complex control scheme had to be split across two controllers or trimmed down; now the same logic fits one base module. Next in importance is the move to float math. On LOGO! 8 every calculation was integer, so fractions had to be scaled by hand (multiply by 10, 100 and keep track of it across the whole program). On LOGO! 9 a pressure value of 4.2 bar or a temperature of 36.6 °C is handled directly.
Inputs and outputs
Locally LOGO! 9 holds up to 64 digital inputs, 60 digital outputs, 16 analog inputs and 16 analog outputs, expansion modules included. On top of that runs the network layer (per integrator documentation): up to 512 network inputs and 480 outputs, plus 128 analog each way. So several LOGO! 9 units on one network exchange signals without a separate PLC master. For choosing the right base module against your I/O count, see our guide on PLC expansion modules.
Display and power
Base modules with a screen now carry a colour touch display of 320×240 pixels (2.4 inch) instead of the monochrome one on LOGO! 8. For machine visualisation there is an external TDE text panel, 4.3 inch (480×272), with Ethernet, connected to the base module over a secure channel. Power was left alone: the same 12/24 V DC and 115/230 V AC options, so matching a module to an existing cabinet stays simple.
LOGO! 9 expansion modules
The one genuinely new module in the system is the AM4 analog module; the rest of the LOGO! communication line stays compatible with the new base module. Worth knowing:
- AM4 — a new analog expansion module with selectable resolution and fractional-value support; it pairs with the LOGO! 9 float math.
- CIM — a communication module for remote connectivity: Modbus, mobile (4G/LTE) and SMS for telemetry and controlling a site from a distance.
- TDE — an external 4.3-inch touch panel (480×272) with Ethernet for local visualisation.
- CSM — a 4-port unmanaged switch to tie several LOGO! units and a panel into one network.
- CMK2000 — a gateway into the KNX system for smart-building and building-automation integration.
For links to drives, meters and sensors through the CIM, Modbus is the usual choice — how it works is covered in our guide on Modbus RTU and TCP for PLCs.
LOGO! Soft Comfort V9 and Web Editor
LOGO! 9 is programmed in the free LOGO! Soft Comfort V9 — and for the first time it is fully cross-platform. Engineers on macOS or Linux used to keep a separate Windows machine; now V9 installs on Windows, macOS and Linux, and a project moves between systems without conversion. One detail for current LOGO! users: the same V9 programs both LOGO! 8 and LOGO! 9 — you pick the controller when you create the project.
- Web Editor — a built-in web-visualisation editor with simulation: build the operator screen with the mouse and check the logic before any hardware is wired.
- UMAC — user management with four access roles, from administrator to operator. Handy when one person commissions and another changes setpoints.
- Simulator — test the program, the display and the network exchange offline, with no controller on the bench.
Logic is built in the familiar LOGO! languages — function block diagram (FBD) and ladder (LAD). If you are new to controller programming, start with the basics in our article on PLC programming languages under IEC 61131-3.
Cybersecurity: secure boot, UMAC and the CRA 2027 rules
Security is the part where LOGO! 9 changed on principle, and not only for marketing. In 2027 the EU Cyber Resilience Act (CRA) takes effect, requiring industrial devices to be protected out of the box. So LOGO! 9 is built secure-by-default:
- Secure boot — the controller checks firmware integrity at every start and will not run third-party code.
- Services on demand — the web server, Modbus and MQTT are switched on deliberately, for a specific task. Fewer open ports mean a smaller attack surface.
- First-boot wizard — on first power-up the device asks for an administrator password, a name and an IP address. The default factory password that people forget to change is gone.
- Firmware updates go through Soft Comfort, and a factory reset keeps the assigned IP — useful for remote sites.
A practical tip from our own work: set a static IP right away and enable only the services you actually need. On a remote pump station DHCP will reshuffle the address sooner or later — and access drops at the worst moment.
LOGO! 8 compatibility and project migration
You can move from LOGO! 8 without rewriting programs from scratch: Soft Comfort V9 imports old projects automatically, and, according to Siemens, the large majority of cases convert with no manual work. Three things need attention — converting integer calculations to float, reformatting the old LCD layout for the new colour screen, and checking the compatibility of existing expansion modules, since the LOGO! 9 hardware platform is updated. A complex machine is still worth checking in the simulator before commissioning.
Is there any rush? LOGO! 8 is not gone yet. According to Siemens plans, it is being phased out of ordering over the coming years (depending on the version), while spare parts and technical support are guaranteed for about another 10 years after phase-out. So existing LOGO! 8 systems will work for a long time.
For new projects taking LOGO! 9 from the start makes sense, while LOGO! 8 stays a valid choice where you need to match an already installed controller exactly. If you are still weighing LOGO! against a larger PLC, compare the approaches in how to choose a PLC and Siemens S7-1200 PLC.
Which LOGO! 9 to buy now
The base module Siemens LOGO! 9 230 RCE (6ED1052-1FB08-0BA3) is already on sale in Ukraine at UAH 9,108: 8 digital inputs, 4 relay outputs, 115/230 V AC power, Ethernet, MQTT support and 800 blocks of memory. It is the workhorse for building automation and small machines — the same format as the popular LOGO! 8, with new internals. The full Siemens LOGO! 9 catalogue keeps growing with new versions, so if you need a different voltage or output type, write to us and we will bring it in.
If a project has to close today, or you need to repeat an existing controller, we keep the full Siemens LOGO! 8 catalogue in stock (30+ versions from UAH 3,832) and the wider Siemens PLC range. Not sure which module fits your I/O and power — write to us and we will check it against the datasheet.
