Digital 800-W bulk front-end power supply meets 80 PLUS Gold standard efficiency

December 06, 2012 // By Paul Buckley
Emerson Network Power’s new 800-W bulk front-end power supply meets the 80 PLUS Gold standard for efficiency. The DS800SL-3 power supply has a high efficiency of 92 percent when operating at half-load from a 230 Vac input.

The device also produces a typical power factor in excess of 0.99.

With a high power density of 19.05 W/in3 (1.16 W/cm3) in a slim-line rack-mounting package, DS800SL-3 power supplies enable system designers to minimize space requirements in enterprise servers and similar space-constrained applications.

The new DS800SL-3 is a fully digital design; it features a built-in I2C serial bus interface and uses the industry-standard PMBus communications protocol. Developed primarily for systems employing distributed power architectures, the power supply has a wide input voltage range of 90 to 264 Vac and is rated for 800 watts output power. The main 12 Vdc payload output is programmable by plus/minus 10 percent, and can deliver up to 65.7 A continuously. An auxiliary ‘always on’ 5 Vdc output, rated at 2.4 A, is also provided for powering server management circuits. Both outputs are tightly regulated, have no minimum load requirement, and offer remote sensing – the 12 Vdc output can compensate for a load bus drop of up to 200 mV.

Opposite-end ac input and dc outputs facilitate fast replacement in the field, and the dc output card edge connector is compatible with the Intel® standard for high availability power supplies for the always-on enterprise market. The power supply features built-in Oring and active load sharing facilities, and supports hot swap operation for fault tolerant and N+1 redundancy applications, allowing as many as six power supplies to be connected in parallel. Up to four DS800SL-3 power supplies can be programmed to share current from their 12 Vdc outputs; if each power supply is delivering 40-50 percent of its rated output to the load, current will be shared to an accuracy of 5 percent, simplifying users’ implementation of high availability power schemes significantly.

The power supplies have an operating temperature range of -10 to 50 degrees Celsius with no derating, and feature a built-in cooling fan with automatic speed control; forward and reversed airflow versions