In other words, the PMU-27V155WCCA is a buffer power supply (DC-UPS) with on-site installation from Delta Electronics. It provides a silent DC output with automatic battery switching in case of a power outage. The input characteristics are adjustable between 100–120 VAC or 200–240 VAC (range 90–132 / 180–264 VAC), 50–60 Hz. The rated output falls within the 27 V category (adjustable 24–28 V), with a nominal value of approximately ~27.6 VDC. The maximum output power reaches 151 W. The battery charging current is adjustable from 0.5–1.5 A.

It includes built-in protections: over-discharge, reverse battery connection, overvoltage, overload, overheating. Status indicators include LED DC-OK (green) and LED reverse battery (red); terminals for external indicators of AC and low battery.

Mechanical dimensions: 178 × 97 × 38 mm, weight approximately 600 g. High efficiency (>88% at 115 VAC, >89% at 230 VAC). Compliant with relevant EMC/EMI standards. Batteries are not included.