Wladimir PoljakovWladimir PoljakovIndustrial Automation Specialist

Hardware / Software / Knowledge

Technical documentation

The memory
of the machine.

A machine must make sense to more than the person who programmed it.

I create and update electrical drawings, control system descriptions and project records for PLCs, HMI and drives — for operation, diagnostics and future changes.

Discuss documentationView projects
PA / ENGINEERINGSheet 01 / 08

Control system

Technical concept sketch

PLCHMII/ODRIVE
ProjectPA-260XX
RevisionV1.3
Sheet01
RevisionV1.3

An illustrative structure, not a real customer document.

PLC / HMI / I/O

Connections. Functions. Versions.

PA—DOC / 01
01

From equipment to a project that makes sense.

Each part of the machine has a place in the records. Together, these documents connect electrical hardware, software and process function.

EquipmentRecord and connectDocumentation
Motor
Electrical drawing
PLC
Project and backup
HMI
HMI project
Drive
Parameters
Sensors
I/O list
Cabinet
Terminals and components
Network
Communication structure
Functional descriptionVersion and changes

The scope and level of detail depend on the task and agreement.

The records must match reality.

A drawing that no longer matches the machine offers little help. Changed wiring, a replacement component or a software revision should leave a traceable record.

  1. 01Cabinet modified
  2. 02Components replaced
  3. 03Software changed
  4. 04Records updated?

Having a folder is not enough. Its contents must belong to a known machine configuration.

02

Which revision is actually current?

Select a drawing, PLC or HMI revision. The current set is predefined for this example; individual project parts can have different version numbers.

Demonstration examplePA-260XX / REV

Electrical drawing

Current in this exampleV1.3

This revision belongs to the current example set. In a real project, its status and correspondence with the machine are verified.

PLC project

Current in this exampleV2.3

This revision belongs to the current example set. In a real project, its status and correspondence with the machine are verified.

HMI project

Current in this exampleV1.8

This revision belongs to the current example set. In a real project, its status and correspondence with the machine are verified.

The highest number alone does not prove that a file is current. A defined set, a traceable status and a check against the actual machine are needed.

03

One project. A structured set of records.

Open a section and select a file. This is one way to organize a technical handover.

PA-260XXExample project structure · no customer data
Electrical03
PLC01
HMI01
Drives01
Network01
Description01
Example content
PDF / Demonstration example

Power circuits

Main_Circuit_V1.3.pdf

Connections between electrical loads, circuitry and equipment identifiers.

PDF / Demonstration example

Control circuits

Control_Circuit_V1.3.pdf

Control circuits, terminals and device connections.

XLSX / Demonstration example

I/O list

IO_List.xlsx

Signals, channel assignments and equipment references.

ZIP / Demonstration example

PLC project

PLC_V2.3.zip

Source project, revision and notes on the required engineering environment.

ZIP / Demonstration example

HMI project

HMI_V1.8.zip

Visualization project, tags and operator interface functions.

PDF / Demonstration example

Drive parameters

Drive_Parameters.pdf

Agreed settings linked to the particular drive and motor.

PDF / Demonstration example

Network structure

Network_Overview.pdf

Devices, interfaces and data exchange structure.

PDF / Demonstration example

Functional description

Functional_Description.pdf

Operating modes, sequences, operational interlocks and function descriptions.

Illustrative preview only. Not a real PDF, backup or downloadable project.

This demonstrates a possible filing structure. There is no portal, file upload or storage of customer data here.

04

What can the documentation include?

Open a technical sheet. The actual set follows from the available information and the agreed project scope.

01

Electrical drawings

Power and control circuits

Sheet 01 / 06
  • I/O and channel allocation
  • Terminals and connections
  • Cabinet components and field devices
02

PLC / software

A traceable software baseline

Sheet 02 / 06
  • Current project and backup
  • Version and comments
  • Structure and required interfaces
03

HMI / SCADA

Operation and visualization

Sheet 03 / 06
  • Project, tags and screens
  • Messages and alarms
  • User and access concept for the task
04

Drives

Settings in the context of the machine

Sheet 04 / 06
  • Drive type and motor data
  • Relevant settings and control method
  • Communication and parameter backups where included
05

Network / communication

Traceable data exchange

Sheet 05 / 06
  • Devices and interfaces
  • Bus and connection structure
  • Required addresses and channel assignments
06

Functional description

What the machine does and why

Sheet 06 / 06
  • Operating modes
  • Sequences and operational interlocks
  • Core functions and transition conditions

Not every project includes every item. Scope, formats, source files and handover arrangements are agreed in advance.

05

The drawing is a map of the machine.

From a signal to a real device, and back. Select a route or hover over it.

Equipment
Connections in the recordsREF / 01–03

Motor

  1. 01Q1.1
  2. 02Intermediate control
  3. 03Contactor K1
  4. 04Motor M1

The drawing associates the PLC command with contactor control and the relevant motor. The power circuit is considered separately.

Analog signal

  1. 01Sensor B1
  2. 02Terminals X1
  3. 03Input AI1
  4. 04Value in the PLC

A channel description connects the sensor, wiring, input and physical meaning of the value in the program.

Valve

  1. 01PLC output
  2. 02Terminals X2
  3. 03Coil Y1
  4. 04Valve

Device identifiers make the connection between a software command, wiring and actuator traceable.

Technical concept sketch / PA-260XX

Simplified functional illustration with fictional identifiers. Not an installation drawing or a description of safety circuits.

06

Have the records fallen behind the machine?

After several repairs and modifications, the project may no longer represent reality. Work begins with the available records and the accessible equipment condition.

How the gap develops
  1. 01Drawing V1
  2. 02Several modifications
  3. 03Changed actual configuration
How it is addressed
  1. 01Survey and assessment
  2. 02Check against the machine
  3. 03Update the agreed records

Reconstruction feasibility and scope are assessed first. Complete recovery of every unknown legacy system cannot be promised.

07

The next engineer must understand the working program.

Years later, it matters not only that a function works, but why. Clear structure preserves knowledge about the machine.

  • Symbolic names
  • Meaningful comments
  • Clear functional groups
  • Traceable data and interfaces
  • A defined current version
PLC / Demonstration exampleREV 2.3
01Operating modes
02Sequence
03Diagnostics

General professional principles only. Internal programming standards and customer source code are not published.

08

Every change should leave a trace.

More than a file number: what changed, why it changed and which machine state it belongs to.

Example version structureREV / LOG
  1. V1.0Initial start-up
  2. V1.1Sensor added
  3. V1.2Drive logic changed
  4. V1.3HMI screen added
  5. V1.4Current set checked

Fictional history of a separate example. It does not represent a customer or the version numbers used above.

09

Knowledge that keeps working.

01

For diagnostics

An up-to-date drawing helps trace where a signal comes from. Without it, connections, wiring and their relationship to the software must be established again.

  1. Signal
  2. Terminal
  3. PLC input
  4. Logic
Fault diagnostics

Documentation can reduce the search effort. No specific time saving is promised.

02

For modernization

Migration starts with understanding the existing system. Known I/O, loads, hardware, communication and functions make changes easier to prepare in a controlled way.

  1. I/O
  2. Hardware
  3. Communication
  4. Function
Modernization
AS-BUILT

Record what was actually built.

Changes made during commissioning need to be captured. Here, as-built means that the records reflect the actual implemented configuration within the agreed scope.

Commissioning
PA / Sheet 08Demonstration example
  1. 01Draft
  2. 02Checked
  3. 03Current set

An example review process, not acceptance of a real project. The scope and handover of as-built records depend on the task.

10

Documentation in real projects.

Actual chipboard transport and packaging line from Case 003
Equipment photograph from published Case 003.
Case 003 · Packaging line · 2026

From PLC/HMI to the operator manual.

PLC software and HMI were developed for a chipboard transport and packaging line. Documentation and an operating manual were handed over after commissioning.

  • Siemens S7-1215 / 7″ HMI
  • TIA Portal / WinCC
  • Manual and documentation handed over
Read the case
Control cabinet from published Project 006
Equipment photograph from Case 006; confidential project records are not shown.
Case 006 · Communication · 2026

Clear modification instructions for remote delivery.

Replacing Weidmüller with ОВЕН ПЛК210 involved electrical drawings, connection diagrams, and dismantling and modification instructions. These supported the customer technicians working under remote guidance.

  • CODESYS V3.5 / Siemens S7-1500
  • Modbus RTU / TCP
  • Circuit, connection and modification records
Read the case
Demonstration example

Which file can you identify clearly?

A small example from a project folder. Choose a filename.

Choose a name to compare.

Even a good name does not prove a file is current. It must match the verified machine state. All filenames shown are fictional.

11

Before the project starts

Can existing machine documentation be updated?

Yes, the task is assessed after reviewing the original records and equipment condition. Hardware and software access, survey effort and project boundaries determine what can be done.

Can everything be reconstructed if the records are lost?

That cannot be promised in advance. Available drawings, hardware, identifiers, programs and survey access are checked first. The feasible scope follows from that assessment.

Does every project include the full example package?

No. Drawings, PLC/HMI projects, parameters, I/O lists, descriptions and other records are included within the agreed scope. Formats and source-file handover are discussed separately.

Does the highest version number automatically mean current?

Not necessarily. The current set must be associated with the actual machine and have a traceable status. A number and date help identify a file but do not replace verification.

Is this already a customer portal?

No. The folders and file previews only demonstrate a possible structure. There is no sign-in, upload, customer file storage or download of real projects.

Connections. Functions. Versions.

Records for a new project — or clarity in an existing one?

Send the materials you already have. Reviewing them will help define what documentation needs to be created or updated.

  • Existing drawings
  • PLC/HMI project
  • Cabinet photographs
  • Equipment list
  • Description of modifications
Discuss documentationView projects

First assess the source information and scope. Then agree the documentation set.