How to specify an industrial control panel
Specify the control panel through its loads, operator modes and interfaces. Add documentation and acceptance requirements to make proposals comparable.
Operator command and status
Control logic
Action on the process
Measured state returns to the PLC
Feedback: sensor → PLC → actuator
Define the panel through the process
Cabinet dimensions and a PLC brand are not the starting point. Describe the controlled equipment, operator actions, automatic sequences and required states first. New assembly, restoration of an existing panel and integration of an additional unit have different scopes. State the chosen boundary and identify who supplies the process description that the controls must implement.
Requirements matrix
| Section | Information to complete |
|---|---|
| Loads | Equipment tag, supply in V/Hz, power in kW, duty and drive requirements. |
| Environment and location | Temperature, dust/moisture, entry direction, space limits and maintenance access. |
| Signals and interfaces | I/O list, complete device codes, communication protocol and connected-system owner. |
| Acceptance and documents | Drawings, BOM, software copy, labelling, verification plan and training scope. |
Engineering determines applicable requirements
IEC 61439 addresses low-voltage assemblies, while IEC 60204 addresses electrical equipment of machines. The general rules in IEC 61439-1 apply together with the relevant part for the assembly type. The responsible designer must establish which parts and editions apply to the project. Listing a standard number does not replace the verification plan and evidence. Agree who produces, reviews and retains that evidence.
Describe protective and interlocking functions as separate requirements. Define their purpose, responsible team and validation method before authorising changes to the existing design.
Illustrative extension to another workshop area
When adding another workshop area, do not estimate available panel capacity from a photograph. Supply the load schedule, current drawing, installed components and software interfaces. Require the proposal to distinguish retained, modified and newly added parts. Have the technical owner approve deviations and confirm the updated handover documentation before construction begins.
Production automation
Connect equipment, controls and software around the functions your production process needs.
Explore the technologies
Putting it into practice
MirAmir: control systems for two workshops
Design and assembly of power supply, control and protection systems for two MirAmir production workshops by Sofcon and partner contractors.
Təhsil Nəşriyyat: printing equipment controls
Restoration of binding and printing machine controls and protection with partner contractors, including a new second panel for the binding machine.