Uninterruptible dc power supply

Siemens Energy & Automation Inc. Sitop UPS500S capacitor-based dc uninterruptible power supply (UPS) provides a 24 V dc backup without requiring a connected battery. It saves significant maintenance time and cost associated with battery replacement and power interruptions, company says. This is a Control Engineering North American print edition Product Exclusive.
By Control Engineering Staff June 30, 2009

Sitop UPS500S capacitor-based dc uninterruptible power supply (UPS) from Siemens Energy & Automation Inc. provides a 24 V dc backup without requiring a connected battery, saving significant maintenance time and cost associated with battery replacement and power interruptions, company says. Advanced systems depend on industrial PCs, PLCs, and other 24 V dc intelligent devices to shutdown in a normal sequence so they can restart without errors. Sitop UPS500S protects valuable PLC and PC-based controllers from erratic power outages by giving enough time for a proper shutdown.

Siemens Energy & Automation introduces Sitop UPS500S, a capacitor-based dc uninterruptible power supply (UPS).
Siemens Energy & Automation introduces Sitop UPS500S, a capacitor-based dc uninterruptible power supply (UPS).

Although Sitop UPS500S does not have the longer backup time of a large battery-based dc UPS, it offers ample time for a proper controller shutdown sequence based on the typical 9 to 3.5 minutes for 1-3 Amp loads. Additionally, its recharge time is less than half its discharge time, meaning the automation system is continuously protected against a possible series of intermittent power outages. Rated for up to 8 years continuous service, the long-life capacitor design can operate safely up to 60°C whereas most traditional UPS batteries can only safely function up to 40°C. Testing has demonstrated it can operate with at least 80% capacity up to 50 °C.

Compact design enables users to safely increase their systems’ reliability while lowering maintenance and enclosure costs. Industrial grade double layer capacitors eliminate the need for the periodic battery replacement and the enclosure ventilation for possible volatile gas emissions from a failed battery required for the old dc UPS systems. Sitop UPS500S comes in 2.5 kW and 5 kW models, with compact DIN rail mount designs with same dimensions as the Sitop Modular 24 V dc power supplies for easy installation and wiring. All Sitop UPS500S and UPS501S products are designed with a rugged IP20 case and certified with standard industry agency approvals, including UL 508, CSA, and CE compliance.

www.sea.siemens.com

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