UL 1558 Switchgear & Medium-Voltage Switchgear for North American Projects
Engineered low- and medium-voltage switchgear solutions for North American industrial, commercial, utility and infrastructure projects, with project-specific configurations from 1kV to 38kV.
Custom UL 1558 Switchgear Manufacturing
As a China UL switchboard manufacturer, RICHES POWERTECH® manufactures custom low-voltage metal-enclosed switchgear for North American industrial, commercial, utility and infrastructure applications.
UL 1558 switchgear is engineered according to the applicable project specifications, equipment ratings and certification requirements. Configurations may include drawout or fixed circuit breakers, copper bus systems, metering, protection, control and auxiliary equipment.
In addition to our UL 1558 low-voltage switchgear capabilities, RICHES POWERTECH® also provides engineered medium-voltage switchgear solutions for applications ranging from 1kV to 38kV, subject to the applicable project standards and certification requirements.
If you are specifying switchgear for a North American project, send us your single-line diagram or equipment schedule. Our engineering team will respond within 24 hours with a technical review and quotation.
Low- and Medium-Voltage Switchgear from 1kV to 38kV
RICHES POWERTECH® provides engineered switchgear and power distribution solutions for low- and medium-voltage applications ranging from 1kV to 38kV, depending on project requirements and applicable standards.
Our product and engineering scope can support project-specific configurations across multiple voltage classes, including 1kV, 2.4kV, 4.16kV, 6.6kV, 11kV, 13.8kV, 24kV, 27kV, 33kV and 38kV applications.
The applicable standard, certification pathway and technical requirements depend on the voltage class, product construction and project specification. We coordinate engineering, testing and certification support according to each project's specific needs.
Typical Voltage Classes
1kV–1.2kV
Low-voltage / high-voltage boundary applications depending on applicable code and project classification
2.4kV–2.5kV
Medium-voltage industrial distribution
4.16kV–5kV
Medium-voltage motor and power distribution
6.6kV–7.2kV
Industrial and infrastructure power distribution
11kV–12kV
Medium-voltage distribution systems
13.8kV–15kV
Industrial, utility and renewable energy applications
24kV–27kV
Medium-voltage utility and industrial distribution
33kV–38kV
Higher-voltage medium-voltage applications
Note: These voltage classes represent typical project-specific applications. The applicable standard and certification pathway depend on the voltage class, product construction and project requirements. Not all voltage classes are covered by a single standard.
UL 1558 Low-Voltage Switchgear
UL 1558 metal-enclosed switchgear is designed for 600V-class low-voltage power distribution applications. Common system voltages include 208Y/120V, 480Y/277V, and 600V three-phase, 60Hz.
The switchgear provides a higher degree of structural integrity and compartmentalization compared to open-frame switchboards, making it suitable for applications where enhanced protection and maintenance access are required.
Key Features
- ● Low-voltage metal-enclosed switchgear
- ● Main incoming circuit breakers (ACB)
- ● Drawout or fixed circuit breakers
- ● Busbar systems (copper or aluminum)
- ● Feeder breakers
- ● Metering and instrument transformers
- ● Protective devices and relays
- ● Main-tie-main configurations
- ● Custom lineups per project SLD
- ● Project-specific engineering
Switchgear Ratings and Configurations
| Parameter | Specification |
|---|---|
| Standard | UL 1558 (Metal-Enclosed Switchgear) |
| Voltage Class | 600V class (project-specific) |
| Frequency | 60 Hz |
| Phase | 3-phase, 3-wire or 4-wire |
| Bus Rating | 600A – 4000A continuous (project-specific) |
| Short-Circuit Rating | Project-specific, based on system design and protective devices |
| Circuit Breaker Type | ACB, drawout or fixed-mounted |
| Enclosure | NEMA 1 / NEMA 3R (project-specific) |
| Internal Separation | Per applicable project requirements |
| Control Power | 120V AC or 125V DC typical |
| Bus Material | Copper busbar; aluminum busbar where specified |
Typical configurations may include the above ratings. Specific ratings are determined by project requirements and final configuration.
Medium-Voltage Switchgear for 1kV–38kV Applications
RICHES POWERTECH® provides project-specific medium-voltage switchgear solutions for applications from 1kV to 38kV. Medium-voltage switchgear configurations may include the following components and features:
Metal-Enclosed Switchgear
Grounded metal enclosures with compartmentalized construction for enhanced safety and structural integrity.
Metal-Clad Switchgear
Removable shuttered assemblies with separate compartments for instruments, relays, bus and circuit breakers.
Drawout Circuit Breakers
Vacuum circuit breakers in drawout configuration for rapid maintenance replacement without disconnecting primary conductors.
Fixed Circuit Breakers
Vacuum circuit breakers in fixed-mounted configuration for applications where breaker removal is infrequent.
Vacuum Circuit Breakers (VCB)
Medium-voltage vacuum interrupters for switching and protection, providing long mechanical and electrical life.
Load Interrupter Switches
Medium-voltage load interrupter switches for switching applications where full fault-current interruption is not required.
Busbar Systems
Copper or aluminum bus systems with project-specific ratings for continuous current and short-circuit withstand.
Current Transformers (CT)
Instrument current transformers for metering, protection and monitoring of medium-voltage circuits.
Potential Transformers (PT/VT)
Voltage transformers for metering, synchronism check and protective relay voltage input.
Protective Relays
Microprocessor-based protective relays for overcurrent, ground fault, differential, distance and other protection functions.
Metering Systems
Power metering, energy metering and demand metering for medium-voltage circuits with communication capabilities.
Surge Protection
Metal-oxide surge arresters for protection against switching surges and lightning transient overvoltages.
Grounding Systems
Grounding switches, grounding resistors and grounding transformers per project requirements.
Protection and Control
Integrated protection, control and SCADA-ready systems for remote monitoring and automated switching.
Configurations and component selection depend on the project voltage class, applicable standards and specific requirements. Final ratings and certifications are determined per project specification.
Switchgear Ratings and Configurations
Low-Voltage (UL 1558)
- ● Voltage: 208Y/120V, 480Y/277V, 600V class
- ● Bus rating: 600A, 800A, 1200A, 1600A, 2000A, 2500A, 3000A, 4000A
- ● Main breaker: ACB (drawout or fixed)
- ● Feeder breakers: ACB, MCCB
- ● Bus material: Copper busbar; aluminum where specified
- ● Enclosure: NEMA 1 (indoor), NEMA 3R (outdoor)
- ● Frequency: 60 Hz, 3-phase
- ● Indoor or outdoor installation
Medium-Voltage (1kV–38kV)
- ● Voltage: 1kV, 2.4kV, 4.16kV, 6.6kV, 11kV, 13.8kV, 24kV, 27kV, 33kV, 38kV
- ● Continuous current: Project-specific
- ● Short-circuit rating: Project-specific
- ● Circuit breaker: Vacuum circuit breaker (VCB), drawout or fixed
- ● Bus material: Copper or aluminum busbar
- ● Enclosure: Metal-enclosed or metal-clad
- ● Protection: Overcurrent, ground fault, differential, distance
- ● Indoor or outdoor installation
Typical configurations may include the above ratings. All ratings are project-specific and subject to the applicable standards and certification requirements.
Protection, Metering and Control
Protection Systems
- ● Microprocessor-based protective relays
- ● Overcurrent protection (50/51)
- ● Ground fault protection (50N/51N)
- ● Differential protection (87)
- ● Distance protection (21)
- ● Bus differential protection
- ● Arc flash detection
- ● Surge protection (arresters)
Metering and Instrumentation
- ● Current transformers (CT)
- ● Potential transformers (PT/VT)
- ● Power and energy metering
- ● Demand metering
- ● Power quality monitoring
- ● Analog and digital instruments
- ● Communication-enabled meters
- ● SCADA-ready interfaces
Control and Communication
- ● Control power supplies (120V AC, 125V DC)
- ● Battery charging systems
- ● Trip units and shunt trip
- ● Close and trip coils
- ● Mechanical and electrical interlocks
- ● SCADA communication (Modbus, DNP3, IEC 61850)
- ● Remote monitoring and control
- ● Automatic transfer schemes
Switchgear Applications
Industrial Facilities
Main incoming and unit substation power distribution for manufacturing plants and process industries.
Data Centers
Medium-voltage utility intake, generator tie and distribution for Tier III and Tier IV data center architectures.
Utility Infrastructure
Utility distribution substations, capacitor bank switchgear and feeder switchgear for electric utility systems.
Solar Power Plants
Medium-voltage collector switchgear for utility-scale PV systems, connecting inverters to the utility grid.
Renewable Energy Systems
Switchgear for wind farms, hydroelectric plants and other renewable generation interconnection points.
Battery Energy Storage (BESS)
Medium-voltage switchgear for battery energy storage system AC collection and grid interconnection.
Commercial Facilities
Service entrance and distribution for large commercial complexes, hospitals, universities and campuses.
Oil & Gas Facilities
Switchgear for drilling rigs, refineries, petrochemical plants and LNG facilities.
Mining Operations
Medium-voltage power distribution for mining operations including mills, conveyors and processing plants.
Water & Wastewater
Power distribution for large pump stations, treatment plants and municipal infrastructure.
Transportation Infrastructure
Traction power and facility power distribution for rail transit and transportation systems.
Large Motor Loads
Motor starting and protection switchgear for large industrial motors, compressors and pumps.
North American Engineering and Compliance Support
RICHES POWERTECH® provides engineering and compliance support for North American switchgear projects. Our services are designed to support project-specific engineering review and AHJ requirements.
Specification Review
Review of project specifications, single-line diagrams and equipment schedules to identify voltage class, ratings and protection requirements.
Short-Circuit Evaluation
Short-circuit current calculation and verification that all equipment ratings meet or exceed the available fault current at the installation point.
Protection Coordination
Review of protection and coordination requirements, relay settings and selective coordination between upstream and downstream devices.
Component Selection
Selection of circuit breakers, protective relays, instrument transformers and other components based on project specifications.
Busbar and Enclosure Design
Busbar sizing, enclosure configuration and NEMA rating determination based on installation environment and project requirements.
Control and Metering
Integration of control power systems, metering, protective relays and SCADA communication interfaces.
Factory Testing
Factory acceptance testing including insulation resistance, contact resistance, primary injection testing and functional verification.
Third-Party and NRTL Support
Project-specific third-party testing, NRTL certification pathway, field evaluation and AHJ documentation support as required.
Final certification, inspection and AHJ acceptance are subject to the applicable project specifications, codes, standards and authority having jurisdiction. Project-specific third-party testing, NRTL certification, field evaluation or other certification pathways may be coordinated according to project requirements.
Applicable Standards and Requirements
Depending on the product configuration and project requirements, applicable standards may include:
UL 1558
Low-voltage metal-enclosed switchgear
ANSI / IEEE C37
AC high-voltage circuit breakers, switchgear assemblies and related equipment
NEMA
Enclosure ratings, dimensions and performance requirements
CSA
Canadian Standards Association requirements for Canadian projects
IEC
International Electrotechnical Commission standards where specified by project
NEC (NFPA 70)
National Electrical Code installation requirements
NFPA 70E
Standard for electrical safety in the workplace
NRTL Requirements
Nationally Recognized Testing Laboratory certification pathways
Project-Specific
Additional testing, inspection and certification requirements per project specification
Note: The applicable standard for any specific project depends on the voltage class, product construction, installation location and project specification. Not all products are certified to all listed standards. Certification pathways are determined on a project-specific basis.
UL 891 Switchboard vs UL 1558 Switchgear
UL 891 switchboards are generally used for low-voltage power distribution assemblies, while UL 1558 switchgear is designed for low-voltage metal-enclosed switchgear applications with the construction, performance and testing requirements applicable to switchgear.
| Feature | UL 891 Switchboard | UL 1558 Switchgear |
|---|---|---|
| Construction | Open-frame, dead-front | Metal-enclosed, compartmentalized |
| Breaker Type | MCCB / ACB | ACB (drawout or fixed) |
| Breaker Access | Fixed-mounted typical | Drawout or fixed-mounted |
| Compartmentalization | Form 1–4b separation | Full metal barrier separation |
| Maintenance Access | Front/rear access | Individual cell access |
| NEC Article | Article 408 | Applicable project requirements |
Switchgear FAQ
What is UL 1558 switchgear?▾
What voltage ratings are available for your switchgear?▾
Do you manufacture medium-voltage switchgear?▾
Is all 1kV–38kV switchgear UL 1558 Listed?▾
Can you provide 15kV or 38kV switchgear?▾
What is the difference between UL 1558 and UL 891?▾
What is metal-enclosed switchgear?▾
Do you offer drawout switchgear?▾
How is the short-circuit rating determined?▾
What certification and testing support do you provide?▾
Request a Switchgear Quote
Have an SLD, equipment schedule, or project specification? Send it to our engineering team for review. We will respond within 24 hours with a technical review and quotation.
Send Your Switchgear Specification
Send your single-line diagram (SLD) or equipment schedule for a free engineering review and quotation.
Related Pages
- UL 891 Switchboard Manufacturer for US Projects
- Switchboard Manufacturer for EPC Contractors
- How to Choose a UL Switchboard Supplier
- UL 1558 vs UL 891 Comparison
- UL 1558 Switchgear FAQ
- What Is a UL 891 Switchboard?
- UL 891 Low-Voltage Switchboards
- UL 508A Industrial Control Panels
- UL Control Panel Manufacturer for US Projects
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- Contact Engineering Team