UL 891 Low Voltage Switchboards

At ASD, we pride ourselves on our extensive expertise and versatile capabilities in designing, engineering, and manufacturing low-voltage switchboards that meet or exceed UL-891 standards. Our switchboards, ranging from 1200A to 5000A and supporting voltages such as 120/208V, 277/480V, and 600V, are built to provide reliable and customized solutions for a wide array of applications and meet rigorous performance standards from 65kAIC to 200kAIC. Whether for single-tenant or multi-tenant/meter layouts, we design our switchboards with meticulous attention to detail, including steel frame construction, copper bussing, and both front and rear accessibility to suit your specific needs.

ASD switchboards are custom engineered with features to enhance safety, reliability, and functionality. These include service entrance ratings, ground fault protection, energy-reducing maintenance switches, and surge protective devices. Our designs can incorporate manual and automatic transfer schemes, mechanical and electrical interlocks, custom metering and other features.  

Our team has deep experience designing and building gear for retrofit projects, ensuring flexibility and seamless integration into existing systems - even when there are space constraints. With options like NEMA 1 and NEMA 3R enclosures, our solutions are built for diverse environments.

General Specifications (Category | Specifications)

Input Phasing
1PH 3W / 3PH 3W / 3PH 4W
Input Voltages
120/240Vac / 120/208Vac / 277/480Vac / 347/600Vac
Amperage
100A to 6000A
Frequency
60Hz
Standard Connections
L1 L2 L3 N G
Services Entrance
None / Suitable / Rated
Main Incoming Feed
Top Feed or Bottom Feed
Main Incoming Device
Utility Ct / Main Breaker / Main Lug
Main Incoming Terminations
Mechanical or Compression Lugs
Max Available Fault Current
200kA
Bussing
Copper (Silver Plated)
Neutral Bussing
100% / 200%
Enclosure Type
NEMA 1 Indoor / NEMA 3 Outdoor
Accessibility
Front / Rear / Side
Exterior Color
ANSI 61 Gray
Other Features
Drawout Frames, Infrared Windows, Surge Protection Devices, Power Meters, Transfer Schemes

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