CyberPower SMUCB175UAC 175A 3-Phase Circuit Breaker
Overview
The CyberPower SMUCB175UAC is a 175A three-pole input/output circuit breaker designed for 3-phase modular UPS systems. It provides localized overcurrent protection at the UPS cabinet level — a critical safety component in data centers, server rooms, and industrial facilities where 3-phase power distribution requires failsafe isolation. The SMUCB175UAC mounts directly to a standard utility pole or equipment frame and meets international electrical codes including UL489, CSA C22.2, and IEC 60947 standards.
Key Features
- 175A 3-Pole Input/Output Rating: Handles 175 amperes across all three phases — sized for mid-to-large modular UPS deployments where you need protection at the disconnect point without oversizing to the next breaker class. This current capacity eliminates nuisance trips on normal load swings while staying within thermal limits of standard 3-phase distribution panels.
- Modular Form Factor: Designed to integrate directly into 3-phase UPS cabinets and modular power systems. The compact white/gray housing (3.00 × 7.5 × 3.40 inches) fits standard mounting footprints — no custom fabrication needed. Weighs 4.40 lbs, keeping overall system weight manageable even across multiple units.
- Pole-Mount Hardware Included: Ships with all hardware needed to secure the breaker to a utility pole or structural mounting point. No separate bracket purchases or field fabrication — you install and connect immediately upon delivery.
- UL489 and International Compliance: Certified to UL489 (standard for circuit breakers in the US), CSA C22.2 (Canada), CE marking (Europe), and CCC (China), plus IEC 60947-1 and IEC 60947-2 industrial switchgear standards. Meets EN 50581 RoHS directives. Deploy across multi-region installations without recertification concerns — the breaker carries the electrical safety credentials required in nearly every jurisdiction.
- Operating Range 32–104°F (0–40°C): Rated for standard commercial and light industrial environments. The operating humidity spec of 0–95% non-condensing means it handles equipment rooms with typical HVAC control. Operating elevation up to 10,000 feet accommodates high-altitude data centers without derating.
- 1-Year Limited Warranty: Covers manufacturing defects and normal operational failures. Provides peace of mind on a mission-critical component without long-term service contract overhead.
Integration & Compatibility
The SMUCB175UAC is built for 3-phase modular UPS systems from CyberPower and compatible third-party equipment. It serves as a localized overcurrent protection device — install it at the UPS input and output terminals to isolate the UPS from the main distribution panel and load feeders. The 175A three-pole design means it protects all three phases simultaneously; a fault on any single phase trips all three contacts, preventing partial-phase conditions that can damage three-phase motors and power electronics. Coordinate the breaker trip curve with upstream utility disconnects and downstream load breakers to create a coordinated protection scheme — your electrical engineer will specify the exact installation topology based on site load profiles and grid conditions.
What's in the Box
The SMUCB175UAC ships with mounting hardware for pole or equipment-frame installation. No separate brackets, fasteners, or adapters are needed — the kit contains everything required for immediate deployment on a standard utility pole or structural steel.
Frequently Asked Questions
Q: What is the SMUCB175UAC rated for?
A: The SMUCB175UAC is a 175A, 3-pole input/output circuit breaker. The three poles mean it simultaneously protects all three phases of a 3-phase power distribution system — common in data centers and industrial UPS installations.
Q: Can I use the SMUCB175UAC indoors and outdoors?
A: The SMUCB175UAC is rated for indoor/outdoor pole mounting. However, it operates within 32–104°F (0–40°C) and 0–95% non-condensing humidity. It is not sealed for direct rain or submersion — use it in a weatherproof enclosure or utility pole structure that provides protection from water spray and condensation.
Q: Does the breaker come with mounting hardware?
A: Yes. The SMUCB175UAC includes all hardware needed for pole or equipment-frame mounting. No additional brackets or fasteners are required.
Q: What international standards does the SMUCB175UAC meet?
A: The SMUCB175UAC is certified to UL489, CSA C22.2, CE, CCC, IEC 60947-1, IEC 60947-2, EN 50581, and is RoHS compliant. It qualifies for deployment across North America, Europe, and Asia-Pacific regions without additional certification.
Q: What is the warranty period?
A: The SMUCB175UAC includes a 1-Year Limited Warranty covering manufacturing defects and normal operational failures.
Q: What's the maximum operating altitude?
A: The breaker is rated up to 10,000 feet elevation, suitable for high-altitude data centers and mountain facilities without derating.
The SMUCB175UAC is a straightforward three-pole breaker for 3-phase modular UPS cabinets — the kind of hardware you install once and never think about again if the load stays normal. At 175A per phase, this breaker is sized for mid-range 3-phase UPS deployments (roughly 60–90 kVA systems depending on power factor). The three-pole design is the key distinction here: a single fault on any phase trips all three simultaneously, preventing partial-phase scenarios that wreck three-phase motors and variable-frequency drives.
Technical Highlights:
- 175A 3-Pole Rating: Handles all three phases up to 175A continuously. This is not an oversized unit — it's matched to mid-scale modular systems where you don't want the next step up (225A or 250A) creating thermal headroom you'll never use. Proper sizing saves dollars on breaker cost without sacrificing protection margin.
- UL489 + IEC 60947 Dual Certification: Meets both US (UL489) and international industrial switchgear standards (IEC 60947-1/2). This means the breaker's trip curve, contact rating, and fault-interruption capacity are independently verified across two regulatory regimes — no surprises if your facility undergoes insurance audit or third-party compliance review.
- Operating Range 0–40°C with 0–95% Non-Condensing Humidity: Standard commercial environment spec. The non-condensing humidity clause means the breaker is not rated for walk-in freezers or outdoor locations with frost. Install it in a climate-controlled UPS room or utility enclosure, not exposed on a wet pole without shelter.
Deployment Considerations:
- Pole-mount hardware is included, but you still need a qualified electrician to coordinate this breaker with your upstream utility disconnect and downstream load feeders. Trip-curve coordination is essential — a breaker that nuisance-trips on inrush steals uptime; one that won't clear a real fault endangers personnel and equipment.
- The 1-year limited warranty covers manufacturing defects, but does not cover wear-out or field abuse. In a data center environment with stable 3-phase input, you can expect 20+ years of service life before contact wear becomes an issue. However, a breaker that's tripped repeatedly under high fault current will need replacement sooner — keep this in mind if your facility experiences frequent surges or grid instability.
The SMUCB175UAC is the right pick for mid-scale data center or industrial UPS installations where you need reliable 3-phase input/output isolation that meets dual US and international codes. Deploy it with a licensed electrician and coordinate the trip curve with your electrical designer — this is not a plug-and-play device, but once commissioned properly, it delivers years of silent protection.
