Custom UL 891 Switchboards
Engineered to your one-line, built in our facility, and delivered in as few as 4 weeks. Every board ships fully NETA tested with complete documentation.
What Is a UL 891 Switchboard?
UL 891 is the safety standard for dead-front switchboards rated 600 volts or less. These assemblies serve as the main power distribution hub in commercial and industrial facilities, receiving utility or generator feeds and distributing power to downstream panels, motor control centers, and other loads.
Unlike panelboards, switchboards offer higher ampacity ratings, greater flexibility in device selection, and easier access for maintenance. They are the backbone of any serious electrical distribution system. As a dedicated UL 891 switchboard builder, we focus exclusively on designing and manufacturing these assemblies to the highest standards.
Engineered Switchboard Packages
- Voltage: 208V, 240V, 480V, and medium-voltage configurations up to 5kV
- Amperage: 400A to 6,000A bus ratings
- Main Devices: Molded case circuit breakers (MCCB), insulated case breakers (ICB), power circuit breakers (PCB), fusible switches, and bolted-pressure switches
- Metering: Integral metering sections, CT cabinets, and revenue metering provisions
- Options: Surge protection, ground fault, zone-selective interlocking, power monitoring, and remote communications
Why Choose SDF for Custom UL 891 Switchboards?
Major OEMs quote 16-30+ weeks. We deliver fast delivery switchboards in as few as 4 weeks from approved submittals. Every engineered switchboard package includes full submittal drawings, one-line diagrams, bill of materials, and NETA acceptance tested switchboard documentation — so your equipment arrives ready to energize with no surprises.
Ready to Spec Your Switchboard?
Tell us about your voltage, amperage, device selection, and more. We will put together a quote for you.