An Innovative Approach for U.P.S :Modular Uninterruptable Power Supplies
by Athanasios Bardakis

Modular uninterruptible power supplies is the new way to provide power continuity solutions configured accordingly to the specific customer needs. So, generally two output power supplies are provided: a D.C. Source of 48V D.C.(nominal) and an alternative source of 230 V A C.

Power capacity is upgradeable by adding parallel rectifier units for the 48v D.C. Requirement or by paralleling inverters for the 230V A.C. Output. Both use the same battery bank, which consists of a 48V D.C. Battery pack. Battery packs are sized to the customer needs. An SNMP device provides the link to the network for the status of the whole modular power supply system.

All the units that are used are discrete and all are standard rack mount units. Most of the units can be hot swappable.

GENERAL DESCRIPTION:

Modular uninterruptible power supplies consists of the following:

1. RECTIFIER UNIT.
   
   They are continuously converting the alternative input current (from 230V A.C.) to direct current of 48V D.C. Many units can be connected in parallel for two main reasons:
   
   a) For power upgrade.
   b) For redundancy.
   
   
2. INVERTER UNIT.
   
   They are providing Alternative output current of 230V A.C. for conventional devices. More units can be connected in parallel for redundancy and power upgrades reasons. As a current source for the inverters is used the Output from the 48V D.C. rectifier units and by pass is provided from the mains.
   
   
3. BATTERY BANKS.
   
   Can either be in standard rack mounting casing or can be external. They are charged through the Rectifier units and provide power to the D.C. loads and the A.C. loads through the inverters.
   
   
4. CONTROL UNIT.
   
   Accept control signals mainly from the rectifier unit and the inverter, display locally the status and transfer the information to the SNMP unit.
   
   
5. SNMP UNIT.
   
   Communicates with the control unit and other external devices, then convert and transfer to standard SNMP protocol.  Supervision is achieved distantly from Network Management Stations. Other capabilities are possible, like remote reboot or site surveillance like temperature, humidity, access control etc.
   
   
6. D.C. DISTRIBUTION UNIT.
   
   Distributes the D.C. power to the loads so no other additional customer distribution panels are necessary.
   
   
7. A.C. DISTRIBUTION UNIT.
   
   Distributes the A.C. power and also no additional customer external panels are also necessary.

BENEFITS:

D.C. and A.C. power is available from a single unit. All units are standard rack mount. Configuration is performed accordingly to the customer needs. Power upgrades are possible at any time. Battery backup capacity time can always be expanded. Installation is most easy as all the hardware is transported in individual boxes and assembled on site. Even a customer’s slightly trained technician can perform the installation if necessary. Maintenance is not a problem as all the units are discrete and can be plugged in by hand.

SUPPORT:

Four years guarantee is provided for the system and two years for the batteries. A backup unit is the best way of support.

APPROVALS:

DataLogic is an ISO 9001 certified company and all the units are CE approved.