Bulk front-end power supply touts 92% efficiency

Emerson Network Power has recently unveiled a new 800 watt bulk front-end power supply which meets the 80 PLUS Gold standard for efficiency. Combined with a typical power factor in excess of 0.99, the DS800SL-3 power supply has an exceptionally high efficiency of 92 per cent when operating at half-load from 230 Vac input.

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 per cent, 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.

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 minimise space requirements in enterprise servers and similar space-constrained applications.

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 per cent of its rated output to the load, current will be shared to an accuracy of 5 per cent, simplifying users' implementation of high availability power schemes significantly.

The power supplies have an operating temperature range of -10 to 50°C with no derating, and feature a built-in cooling fan with automatic speed control; forward and reversed airflow versions are available to simplify integration with the rack's cooling layout.

The power supplies are comprehensively protected against fault conditions, including input under voltage, output short-circuit, overload and over-voltage. The power factor correction and output converter stages are both monitored for over temperature conditions, and correct operation of the fan is also checked. DS800SL-3 power supplies have a demonstrated mean time between failure (MTBF) of 100,000 hours, running at full load and 25°C ambient, and are backed by a comprehensive two year warranty.

For additional information, please visit the DS800SL product page.