What Is an Electrical Switchboard?
An electrical switchboard is an installation that brings together the circuit breakers, isolators, fuses, contactors, relays, capacitors, and measuring devices required to distribute, control, and protect a facility’s electrical power within a standard metal enclosure. It safely distributes the electricity coming from the grid to the outputs, automatically disconnects the circuit in faults such as short circuit/overload/earth leakage, and provides centralized control over the system. Electrical switchboards must be designed in accordance with the TS EN 61439-1/2 standard, and must be manufactured by determining short-circuit withstand (Icw), rated current (In), and protection class (IP).
Types of Electrical Switchboards
Depending on their intended use, electrical switchboards are divided into the following categories:
1. Low Voltage (LV) Distribution Switchboard
The main switchboard that distributes the main energy coming from the grid to sub-panels or directly to loads. It includes a on/off switch, fused load break switch, molded case circuit breaker, and compartmentalized busbar system. It is generally manufactured with a current capacity between 100–6300 A.
2. Power Factor Correction Switchboard
By compensating reactive power consumption, it keeps the cosφ (power factor) value in the range of 0.98–1.00. It includes capacitors, contactors, and a reactive power relay controller. It eliminates reactive power penalties and provides 10–30% energy savings.
3. MCC (Motor Control Center)
A switchboard that centrally operates, protects, and monitors a large number of motors. It includes modules such as soft starter, star-delta starter, and frequency inverter (VFD). It is considered the heart of industrial facilities.
4. Automation (PLC) Switchboard
Includes the PLC that automatically manages the production line, an HMI touch panel, I/O modules, drives, and safety relays. It is built with platforms such as Siemens S7-1500, Schneider M580, ABB AC500.
5. Transfer Switchboard (ATS)
A switchboard that automatically transfers to the generator in case of a grid outage. It is mandatory for hospitals, data centers, and critical production lines. Manual or motorized controller options are available.
6. Synchronization Switchboard
A system that synchronously operates multiple generators or generator + grid. It is used for high peak load (peak shaving) and continuous power applications.
7. UPS (Uninterruptible Power) Switchboard
A switchboard that ensures uninterrupted supply to sensitive loads and includes static bypass and a battery bank.
Main Components of an Electrical Switchboard
- Switchboard Enclosure: Sheet-metal enclosure with TSE 4915, IP54/65 protection classes (Rittal, Kemiks, AE series).
- Busbar System: Copper or aluminum, sized according to current capacity.
- Circuit Breakers: Molded case (MCCB), air circuit breaker (ACB), thermal-magnetic or electronic trip unit.
- Load Break Switch / Fused Load Break Switch: Manual isolation with line fuses.
- Contactor and Thermal Overload Relay: Motor control and overload protection.
- Residual Current Device (RCD): Earth leakage protection with 30–300 mA sensitivity.
- Measuring Devices: Multimeter, power analyzer (PM5560, UMG509), current transformer (CT).
- Surge Protection (SPD): Type 1+2 lightning/overvoltage protector.
Switchboard Selection Criteria
- Rated Current (In): What current will it operate at? 100–6300 A.
- Short-Circuit Withstand (Icw): Typically 25–100 kA / 1 s.
- Protection Class (IP): Indoor IP31–IP55, outdoor IP54–IP66.
- Form Class (Form 1–4): Degree of internal segregation.
- Busbar System: Current capacity and phase distribution.
- Brand Preference: Schneider, ABB, Siemens, Legrand, Eaton.
- Test Certificates: TSE, CE, EN 61439-2 type test certificate.
Compliance with the TS EN 61439 Standard
As of 2014, the TS EN 61439-1 (General Rules) and EN 61439-2 (Power Switchgear and Controlgear Assemblies) standards are mandatory in the EU and Türkiye. This standard covers short-circuit withstand, temperature rise, protection class, and dielectric tests. Uncertified switchboard production cannot be legally sold.
DOA Enerji Switchboard Manufacturing
DOA Enerji Aydınlatma manufactures electrical switchboards at its Başakşehir İOSB facilities as an ABB and Schneider Electric approved system partner. LV distribution, power factor correction, MCC, ATS transfer, and automation switchboards are delivered TS EN 61439-1/2 certified, type-tested, and with a 2-year warranty. A project file including a single-line diagram, short-circuit calculation, and thermal calculation is provided free of charge.
Frequently Asked Questions (FAQ)
How long does it take to manufacture an electrical switchboard?
A standard LV distribution switchboard takes 2–3 weeks, a power factor correction switchboard 2–3 weeks, MCC and automation switchboards 4–6 weeks, and special project switchboards 6–10 weeks. An accelerated production option is available for urgent projects.
Which brands should be preferred in switchboard manufacturing?
For A-class manufacturing, Schneider Electric, ABB, Siemens, Legrand, Eaton should be preferred. For the enclosure, Rittal and Kemiks; for busbars, copper E-Cu; and for control, Schneider XB6/XB7 series are standard.
Is a TS EN 61439 certified switchboard required?
Yes, it has been a legal requirement since 2014. In a new electrical installation project, an uncertified switchboard is not accepted by TEDAŞ/BEDAŞ. The type test report, short-circuit withstand test, and temperature rise test must be documented.
How should the switchboard IP protection class be selected?
Indoor office/technical room IP31–IP41, production area IP54, outdoor IP55–IP66, and underwater IP67–IP68 are recommended. For dusty environments, IP5X, and for corrosion resistance, a stainless-steel enclosure should be selected.
What does the price of an electrical switchboard depend on?
Rated current, short-circuit withstand, the brand used, enclosure size, number of circuits, whether automation is included, IP class, and special requirements affect the price. There can be a 10x difference between a 250A standard distribution switchboard and a 2500A main distribution switchboard.