⚡ APC USB to RJ50 UPS Interface Cable
 
(USB Type‑A Male ↔ RJ50 10‑Pin Modular Plug • Smart UPS Communication Cable)

This cable bridges modern USB‑equipped computers with APC UPS units that use a 10P10C RJ50 serial/data port, enabling USB-based monitoring and control without needing a legacy serial interface.
 
🔧 Cable Form
USB Type‑A male (host side)
RJ50 10‑pin modular plug (UPS side)
Cable length: 6ft
Shielded, molded strain relief
APC part numbers: 940‑0127B, AP9827, APC‑USB‑RJ50 (varies by region and model)
 
🖥️ Compatible Devices
APC Smart‑UPS models with RJ50 data ports
Smart‑UPS 750 / 1000 / 1500 / 2200 / 3000
Smart‑UPS RT series
Smart‑UPS XL series
Select Back‑UPS Pro models with RJ50 ports
Host systems:
Windows, macOS, Linux (with PowerChute or native UPS support)
 
✅ Common Uses
🔋 UPS monitoring — battery status, load, runtime, voltage
🧩 Automated shutdown during power loss
🧪 Event logging and alerting for power anomalies
🔧 Firmware updates and UPS configuration
🧵 Replacing legacy serial cables with USB‑based control
 
🧠 Signal Format
⚡ USB 2.0 host side
🔌 RJ50 side carries serial signaling (RS‑232 emulation over USB)
🔁 Emulates COM port via USB CDC driver
📏 RJ50 pinout: 10P10C modular (not interchangeable with RJ45)
 
⚠️ Things to Watch Out For
📉 Not a generic USB‑to‑serial cable — optimized for APC UPS units only
🔌 RJ50 ≠ RJ45 — same shape, different pin count and keying
🧯 Requires APC PowerChute software or compatible UPS monitoring tools
📏 Not compatible with APC UPS units that use DB9 serial or USB‑B ports
 
🛠️ Quick Tips for Beginners
🧭 Confirm your UPS has a RJ50 10‑pin data port
🔌 Install APC PowerChute for full monitoring and shutdown automation
🧪 Use USB CDC driver if PowerChute isn’t available
🧯 Label this cable — RJ50 looks like Ethernet but is not interchangeable