What is a DC-Uniterruptible Power System?


What is a DC-Uninterruptible Power System?


For more information on DC-UPS Products, call us 301-694-9601 or email us

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A DC-UPS is an uninterruptible power system that takes in primary power (usually utility AC) and outputs DC voltage while providing backup power from the integrated batteries in the event the incoming (utility AC) power is lost.

The most common DC (direct current) voltages in use are 48, 24, and 12 volts, but other or multiple voltages are available. SEI DC-UPSs integrate power supplies (rectifiers) and output distribution (busses and cabling) along with the batteries inside the unit to provide non-stop power to end devices, in a single compact, space-efficient unit.

Why not use a regular UPS?

AC-UPSs input AC Power and output AC Power. If your end-point devices require DC input, you must convert the UPS AC output power to DC with a rectifier or a separate AC to DC power supply. This adds costs and requires a larger UPS to account for the power loss in converting to DC.

Are DC-UPSs less costly to operate?

DC power systems are less costly to operate than AC systems. They consume less power since only one internal power conversion (from AC to DC) is needed, as opposed to two internal conversions (AC to DC back to AC) in AC-UPSs. Fewer power conversions reduce the BTUs the system dissipates, thereby reducing cooling requirements. These factors can reduce electrical consumption by up to 25% over AC-UPSs.

How can I remotely manage the DC-UPS?

Our optional Web/SNMP interface is embedded in the system, and will provide information and control over a variety of parameters, including AC Power off, battery test status, voltage and power output levels. SNMP traps can be delivered to a network management system on a host of parameters. It is also a convenient and inexpensive way to perform a hard reboot by turning power off to specific ports. Click here for more information.

Can I customize your UPS?

The modularity of SEI’s line of UPSs allows a high level of customization such as current, voltage, battery backup, and output distribution. Form-Fit factors can be usually adapted within a turn-around period of 30 days. For specific requests, please contact us or click here.

Why buy from SEI?

Founded in 1977, System Engineering International is a leader in critical power systems. Our products power the majority of Digital Centrex phones in the US, as well as providing Power over Ethernet midspan injectors. As a result of our outstanding value and customer support, SEI has sold over 30,000 units to over 1,000 customers. For more information, click here.



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ISDN Power Products and DC UPS Systems from SEI are available on our GSA Contract GS-35F-0487W

For order information or technical support call us at 301-694-9601 or email us using our Contact Us form


ISDN Power Products and DC UPS Systems from SEI are available on our GSA Contract GS-35F-0487W

For order information or technical support call us at 301-694-9601 or email us using our Contact Us form