PLC-Inspector
PLC-Inspector · Modbus/TCP for Siemens LOGO!

Professional PLC Memory Viewer

Monitor and analyse your Siemens LOGO! PLC memory in real time via Modbus/TCP. Available for Mac, iPhone and iPad.

One purchase · all Apple devices · no account required

PLC-Inspector showing the memory view of a Siemens LOGO!
Write access

Set a value, see the effect at once

Write a holding register straight from the memory view and watch in the same window how the controller reacts. Changes are highlighted while they happen.

Because writing moves real machinery, it takes two steps on purpose: switch on write mode, check the value, confirm. If you are commissioning for hours, turn the prompt off for the session. It is back the next time you open the view.

  1. Switch on write mode

    It has to be enabled deliberately and lapses on its own when you leave the view.

  2. Enter the value

    Decimal or hexadecimal. The preview shows both notations and the bit pattern.

  3. Confirm

    The app checks what the PLC mirrors back and reports separately if the confirmation does not match the order.

The write dialog: register VW6 with the new value and a preview in decimal, hexadecimal and bits
Features

Powerful Features

Everything you need to monitor and debug your Siemens LOGO! PLC controllers.

Real-time Monitoring

Auto-refresh from 0.5 to 10 seconds, without requests piling up. You can watch a controller while it works.

Change Detection

Changed registers are highlighted in orange, counted, and you can jump between them with the arrow keys.

Multi-Station Support

Manage multiple PLC stations with custom names and easily switch between them.

LOGO! 8 Support

Full support for Siemens LOGO! 8 (0BA8) over Modbus/TCP. Earlier LOGO! generations have no Modbus interface.

Binary Display

View register values in hexadecimal, decimal and binary format simultaneously for detailed analysis.

Universal App

Buy once, use everywhere: Mac, iPhone and iPad. Available in ten languages.

Universal App

One App, All Your Devices

Monitor your PLCs from Mac, iPad or iPhone. Buy once, run on all your Apple devices.

PLC-Inspector on iPad PLC-Inspector on Mac PLC-Inspector on iPhone

Available on macOS, iPadOS and iOS

Technology

Proven Technology

PLC-Inspector uses binary communication routines for the Modbus/TCP protocol developed by spiritdev. These routines have proven themselves in various industrial applications and guarantee reliable, fast communication with your PLC.

Learn more about spiritdev
Reliability

Trustworthy when it counts

A diagnostic tool is only worth something if you can rely on what it shows.

Error message in plain language: the app explains a timeout and suggests what to check

Complete responses, even for large reads

Up to 125 registers in one go are reassembled correctly, even when the answer arrives split across several TCP packets.

Every answer is matched to its request

A late response to an earlier request can never appear as a current value. In a diagnostic tool that is the worst possible error.

Errors in plain language

Modbus exceptions and connection problems are explained in words instead of an error number.

One connection per station, strictly serialised

A LOGO! tolerates only a single TCP connection. The app respects that and queues its requests.

In Action

Screenshots

See PLC-Inspector in action.

Changed values highlighted in orange for easy identification
Easy station configuration with all Modbus settings
Registers on the iPhone: decimal, hexadecimal and every single bit
Several controllers side by side, switch between them in one tap
Download

Download Now

Universal app for Mac, iPhone and iPad. One purchase, all devices.

Support

Support

Need help? Have questions or suggestions? We are here to help.

support@plc-inspector.com