APC BX850M Line-Interactive Tower UPS 850VA
Overview :
The APC BX850M is a compact line-interactive tower uninterruptible power supply (UPS) designed to provide short-duration backup power and surge protection for desktop systems, networking equipment, and small office electronics. It is commonly deployed by IT administrators and technical users who need protection from power outages, voltage fluctuations, and electrical surges in workstation or small network environments.
The UPS provides 850VA / 510W output capacity, delivering stepped sine-wave output suitable for typical office electronics and consumer networking devices. The system includes Automatic Voltage Regulation (AVR), which stabilizes utility power fluctuations such as brownouts and overvoltage conditions without immediately switching to battery operation. This allows the UPS to preserve battery runtime while maintaining stable voltage output.
For device connectivity, the BX850M includes eight NEMA 5-15R outlets, divided into four battery-backup plus surge-protected outlets and four surge-only outlets. This configuration allows critical devices such as computers and routers to receive battery backup while less critical devices remain protected from power spikes. The UPS operates on a 120V electrical ecosystem and connects via a NEMA 5-15P input plug with a 6-foot power cord.
Within deployment environments, the BX850M is typically used in home office workstations, small business desktops, and network edge equipment setups. Devices such as desktop PCs, broadband modems, routers, NAS devices, and small switches can remain operational long enough for safe shutdown during outages.
The unit includes a front-panel LCD display that provides real-time status information including load level, battery condition, runtime estimates, and utility voltage. USB communication allows integration with APC PowerChute software, enabling automated shutdown of connected systems when battery capacity reaches a defined threshold.
In real-world deployment, the BX850M is commonly used to support a single workstation, router, modem, and small network device, providing several minutes of runtime for graceful shutdown. At full load, runtime is typically around 2 minutes, while moderate loads can extend runtime to roughly 8–9 minutes.
However, this UPS should not be deployed for rack-mounted servers or high-power compute workloads. Its 510W maximum output and tower form factor make it unsuitable for multi-server racks or environments requiring extended runtime or high-density power protection.
Key Features
- 850VA / 510W line-interactive UPS with AVR
- Eight NEMA 5-15R outlets with surge protection
- Four battery backup outlets for critical equipment
- LCD display showing runtime, load, and voltage
- USB interface for PowerChute shutdown integration


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