Eaton 5P1150IRG2 UPS 920 W, line-interactive, rack 1U, 6 × C13

The strength of this UPS is its power-to-size ratio: 920 W of real power fits into a 43.2 mm tall chassis that takes up one rack unit. It is 438 mm wide and 509 mm deep, so check the depth of your cabinet before installing. It weighs 14.2 kg, most of it in the batteries, so it makes sense to mount the UPS low in the cabinet on sturdy rails. The colour is black and silver.

Line-interactive topology means the UPS does not spend battery charge on every small fluctuation. Automatic voltage regulation smooths out input sags and surges, and the unit only goes to battery when the mains fails or the voltage leaves the permitted range. The input operating range is 150–294 V, and the output is held at 200–240 V and 50/60 Hz. The output is a sine wave, just like regular mains power, which also suits more sensitive power supplies.

The manufacturer quotes 98.2 % efficiency and a noise level of 35 dB. High efficiency means the UPS itself wastes little energy and adds less heat to the cabinet, which matters most in a densely packed rack. It is rated for 0–40 °C operating temperature, 0–90 % relative humidity and altitudes up to 3000 m. The battery is a sealed lead-acid (VRLA) type with 9 Ah capacity and 6 V voltage.

Devices plug into six IEC C13 outlets, the same connector found on power cords for servers, switches, storage and firewalls, so your existing cables will usually fit. The UPS itself is powered through an IEC C14 inlet. A device with a regular Schuko plug needs a C14 to Schuko adapter. Six outlets leave enough room for a server with dual power supplies and the network gear behind one UPS.

The UPS has a USB Type-B port and an RS-232 serial interface. Through them a server is notified when the UPS switches to battery, and power management software shuts the system down cleanly before the battery runs out. The LCD display on the front panel shows the status right at the rack. The unit complies with IEC/EN 62040-1, 62040-2 and 62040-3, UL 1778 and CSA-C22.2 and carries CE and UKCA marking. A user manual and a quick installation guide are included.

Businesses with little free space in the server rack but a load reaching several hundred watts; small server rooms where several servers and network devices need shared uninterrupted power; and IT administrators who prefer a quiet, highly efficient line-interactive UPS that occupies just one rack unit.