What Are Switchgear Materials?
Switchgear materials are the general name for all switching, measuring, protection, and control equipment that opens and closes electrical circuits, protects against faults such as short circuit/overload/earth leakage, and provides system control. This concept, whose English equivalent is "switchgear," covers a wide range of equipment such as circuit breaker (breaker), disconnector (disconnector), fuse (fuse), contactor, thermal magnetic relay, residual current device (RCD), surge protection device (SPD), power analyzer, combined meter, current transformer (CT), and voltage transformer (VT). It is divided into two main classes—low voltage (LV) and medium voltage (MV)—and is a fundamental building block of every electrical panel, substation, and distribution facility.
LV (Low Voltage) Switchgear Materials
Equipment used at the 0–1 kV voltage level:
1. Molded Case Circuit Breakers (MCCB)
- Rated current between 16 A and 1600 A
- Thermal (overload) and magnetic (short-circuit) protection
- Adjustable electronic or thermal-magnetic trip unit
- Brands: Schneider NSX, ABB Tmax, Siemens 3VA, LS Susol
2. Air Circuit Breakers (ACB)
- 630 A – 6300 A, used in main distribution boards
- High short-circuit withstand capacity (50–150 kA)
- Microprocessor protection relays (LSIG)
- Brands: ABB Emax 2, Schneider MasterPact, Siemens 3WL
3. Miniature Circuit Breakers (MCB)
- 0.5 A – 125 A, in residential and commercial lighting/socket circuits
- B, C, D trip curves (switching type)
- Versions with residual current protection (RCBO) are available
4. Contactors
- Used for control of motors, heaters, capacitors, and lighting
- 9 A – 800 A, AC1/AC3/AC6 categories
- Brands: ABB AF, Schneider TeSys, Siemens Sirius 3RT
5. Thermal Magnetic Relays
- Protect the motor against overload and phase loss
- Used together with a contactor
6. Residual Current Devices (RCD/RCCB)
- Earth leakage protection with 10–300 mA sensitivity
- Type A, AC, B classes (Type B for DC component)
7. Surge Protection Devices (SPD)
- Type 1 (lightning), Type 2 (transient overvoltage), Type 3 (sensitive load)
- Used on both LV and MV lines
8. Fused Load Break Switches
- NH (knife-blade) fuse type or cylindrical fuse type
- Manual isolation and overcurrent protection
MV (Medium Voltage) Switchgear Materials
Equipment used between 1–36 kV:
1. Vacuum Circuit Breakers (VCB)
- 7.2–40.5 kV, the most common MV breaker type
- Vacuum-bottle design, maintenance-free
- 630 A – 4000 A rated current
- Brands: ABB VD4, Schneider HVX, Siemens 3AH
2. SF6 Gas Circuit Breakers
- Sulfur hexafluoride gas-insulated
- Compact size, suitable for outdoor use
- Being replaced by vacuum breakers due to environmental concerns
3. MV Disconnectors (Disconnector)
- Provides a safe isolation distance for no-load circuit disconnection
- Versions with earthing blades
4. MV Fuses
- High rupturing capacity (HRC) fuses
- For transformer protection and motor protection
5. Current and Voltage Transformers (CT/VT)
- Measurement for meter and relay supply
- Current transformers from 50/5 to 4000/5 A
6. Protection Relays
- Overcurrent (50/51), over/under voltage (27/59), differential (87)
- Modern microprocessor relays: ABB REF615, Schneider Sepam, Siemens Siprotec
Switchgear Brands – Quality Comparison
| Brand | Origin | Strength |
|---|---|---|
| ABB | Switzerland–Sweden | MV systems, contactor |
| Schneider Electric | France | Smart buildings, automation |
| Siemens | Germany | Industrial automation |
| Legrand | France | LV distribution, prefabricated |
| Eaton | USA | Critical power, UPS |
| Mitsubishi | Japan | PLC, drive |
| LS Industrial | S. Korea | Cost-effective premium |
| Türkiye yerli | TR | Federal Elektrik, EAE, Maktek |
Switchgear Selection Criteria
- Rated current (In) and voltage (Un) must match system values.
- Short-circuit withstand capacity (Icu, Icw) must be greater than the facility short-circuit current.
- Selectivity: The upstream breaker must not trip before the downstream breaker.
- Protection class (IP): Must be suitable for environmental conditions.
- Brand compatibility: The same supply channel should be preferred.
- Stock and service: Spare parts must be accessible.
DOA Enerji Switchgear Supply Service
DOA Enerji Aydınlatma, as an authorized supply partner of the ABB, Schneider Electric, Siemens, Legrand, Eaton, LS brands, provides project-based wholesale switchgear supply. All products are delivered with an original invoice, CE/TSE certificate, and manufacturer warranty. For stocked models, the delivery time is 1–3 days; for special-order products, 2–6 weeks.
Frequently Asked Questions (FAQ)
Are switchgear materials and electrical materials the same thing?
No. Electrical materials cover all installation products such as sockets, switches, cables, and luminaires. Switchgear materials refer only to switching, protection, control, and measuring equipment. Switchgear materials are the professional/industrial subset of electrical materials.
Which switchgear brand is better?
It varies by facility type. For automation-heavy projects, Schneider Electric and Siemens; for MV systems, ABB; for motor control applications, ABB AF or Schneider TeSys; for economical solutions, LS Industrial is recommended. A mix of brands is not recommended; for service and selectivity, a single brand should be preferred.
Where can switchgear materials be purchased?
They should be purchased from the manufacturer’s authorized distributor or system integrator. Counterfeit/fake products carry a risk of fire and electric shock. Purchasing should be made from authorized dealers like DOA Enerji with an original invoice and serial number.
How can counterfeit switchgear be identified?
Check the hologram, laser marking, serial number, and verify via the manufacturer’s website. If the price is 30%+ below the market, it may be counterfeit. Ask for certificates and an invoice; gray-market products are products without warranty.
Which certificates are mandatory for MV switchgear materials?
For MV equipment, the IEC 62271 series and for LV the IEC 60947 series standards are mandatory. In Türkiye, TSE and TEDAŞ approval is also required. Uncertified MV switchgear cannot be connected to the grid.