Electrical Panel Design: Technical Details, Programs, and Engineering Principles
An electrical panel is a fundamental piece of equipment that ensures the safe distribution of electrical energy and contains the control and protection components of the system. In many industrial, commercial, and residential applications, especially in low-voltage systems, the installation of electrical panels is critical for energy continuity and safety.
What is an electrical panel and why is it used?
An electrical panel forms the main distribution point for energy entering a building or facility. Energy from the grid is divided here through circuit breakers, contactors, fuses, and relays. In addition to distributing energy, panels:
Provide overcurrent and short-circuit protection.
Optimize energy management.
Increase system traceability.
Offer remote control and automation infrastructure.
Needs Analysis and Load Calculations
Electrical panel design begins by determining the total power of the system, load characteristics (inductive, capacitive), number of phases (single-phase, three-phase), and voltage level (low voltage below 0.4 kV). The following calculations are performed when creating a low-voltage panel diagram:
Active, reactive, and apparent power analysis
Short-circuit calculations
Voltage drop calculations
Selectivity analysis
Creation of Single Line and Detail Diagrams
The following diagrams are typically created in project drawings:
Single Line Diagram
Panel Layout
Wiring (Internal Connection) Details
Electrical Panel Connection Diagram
Software Used in Electrical Panel Design
Electrical panel design is now done more safely, quickly, and in accordance with standards using engineering software that replaces manual drawings. Here are some of the programs commonly preferred in professional projects:
EPLAN Electric P8: One of the most preferred software programs worldwide for industrial automation and low-voltage panel projects. It enables the automatic creation of details such as single-line diagrams, internal connection diagrams, cable lists, and terminal connections. 3D layout plans of panel components can also be created.
AutoCAD Electrical: Significantly shortens panel drawing time thanks to its symbol libraries and automatic numbering features. It offers a drawing infrastructure compliant with standards and provides practical solutions, especially in automation projects.
Caneco BT: Used in low-voltage panel projects for short-circuit calculations, voltage drop analyses, device selection, and protection coordination. It provides a calculation infrastructure that ensures technical suitability when determining electrical panel prices.
SEE Electrical: A program preferred for small and medium-sized panel projects due to its user-friendly interface. It simplifies processes such as cabling, numbering, and labeling.
Schneider Electric EcoStruxure Panel Builder / XLPro³ (Legrand): These tools, specifically developed for manufacturers, simplify the selection of panel components, heat distribution analysis, and layout planning. They also provide advantages in panel pricing and parts list creation.
Electrical Panel Materials and Components
An electrical panel contains various components according to their functional tasks:
Main switches (MCCB, ACB)
Residual current protection relays (RCCB, RCBO)
Fuses and circuit breakers
Contactor, time relay, motor protection switch
PLC, HMI, energy analyzers
Rail type cable trays, terminal blocks
Insulated busbar systems
Grounding busbars and neutral busbars
How to Install an Electrical Panel?
Electrical panel installation is carried out according to the following sequence:
The panel cabinet is placed and secured on site.
Internal components (rails, busbars, insulators) are mounted.
Protection and control elements are installed.
Internal panel wiring is completed, numbered according to the project.
Input and output cables are connected.
Insulation tests and grounding measurements are performed.
Functional tests are carried out before power is supplied.
Electrical Panel Installation and Testing Process
The following tests must be performed before the panel is commissioned:
Insulation test (with Megger)
Continuity test
Grounding test
Functional test (switching on/off under load)
Heating check with thermal camera
Types of Electrical Panels
Electrical panel types according to their areas of use are as follows:
Main Distribution Panels (MDP)
Sub-Distribution Panels (SDP)
Motor Control Panels (MCC)
Compensation Panels
PLC Automation Panels
Meter Panels
Electrical Panel Prices
Electrical panel prices are determined according to the following variables:
Quality of equipment used in the project (brands such as ABB, Siemens, Schneider)
Panel type (wall-mounted, floor-standing, modular systems)
Is installation included or just the panel?
Protection class (IP20, IP54, IP65, etc.)
Size, number of inputs/outputs, and short-circuit resistance
Electrical panel design requires high precision, both in terms of engineering principles and international standards (IEC 61439, TSE, TEDAŞ specifications, etc.). Correct design using modern software tools ensures the safe, efficient, and long-lasting operation of the system. Proper planning regarding both electrical panel prices and installation is a fundamental requirement for the sustainability of the project.