LOW VOLTAGE BATTERY DISCONNECT (LVBD)

///LOW VOLTAGE BATTERY DISCONNECT (LVBD)
LOW VOLTAGE BATTERY DISCONNECT (LVBD) 2017-11-17T23:05:24+00:00

THE LOW VOLTAGE BATTERY DISCONNECT (LVBD) OPTION ADDS A NEW DIMENSION TO BATTERY BACK-UP OF THE TECHNOLOGY DYNAMICS LINE OF HIGH RELIABILITY POWER SUPPLIES. THE DC OUTPUT OF THE POWER SUPPLY SIMULTANEOUSLY CHARGES THE BATTERY AND POWERS THE LOAD. WHEN AN AC INPUT POWER FAILURE OCCURS, THE BATTERY CONTINUES TO POWER THE LOAD WITHOUT ANY POWER INTERRUPTION TO THE LOAD.

THE LVBD MODULE OPTION ELECTRONICALLY MONITORS THE BATTERY VOLTAGE. WHEN THE BATTERY VOLTAGE GOES BELOW A PREDETERMINED (ADJUSTABLE) LEVEL, THE LVBD MODULE AUTOMATICALLY DISCONNECTS THE BATTERY, THEREBY PROTECTING THE BATTERY FROM A COMPLETE DISCHARGE. THIS LEVEL IS USUALLY SET TO CORRESPOND TO ABOUT 1.67 TO 1.7 VOLTS PER CELL OF THE BATTERY.

THERE ARE THREE VERY SIGNIFICANT BENEFITS TO THE USE OF THE LVBD MODULE TO PROVIDE BATTERY BACK-UP. THESE ARE:

  • NO POWER INTERRUPTION WHEN BATTERY OPERATION IS REQUIRED.
  • 100% EFFICIENCY WHEN BATTERY OPERATION IS USED.
  • BATTERIES ARE PROTECTED FROM PERMANENT DAMAGE BY EXCESSIVE DISCHARGE

SINCE THE BATTERY IS CONNECTED ON THE OUTPUT OF THE REGULATED POWER SUPPLY, IT IS NOT POSSIBLE TO OVERCHARGE THE BATTERY. THE USUAL RECHARGE VOLTAGE FOR A SEALED LEAD ACID BATTERY WHEN OPERATED IN A “FLOAT” APPLICATION IS 2.3 VOLTS PER CELL. FOR A TYPICAL 24 VDC APPLICATION, THERE WOULD BE 12 CELLS, THUS 12 TIMES 2.3 VOLTS PER CELL, OR 27.6 VC. THIS CORRESPONDS TO THE POPULAR 28 CELLS OUTPUT.

AFTER A UTILITY POWER FAILURE OCCURS, IT IS NECESSARY TO RECHARGE THE BATTERIES. SINCE THE BATTERIES ARE CONNECTED ON THE OUTPUT BUS, THE RECHARGE OCCURS AUTOMATICALLY. THE BATTERY WILL ONLY BEGIN TO ACCEPT CHARGE WHEN THE DC VOLTAGE GOES ABOVE THE NORMAL OPEN CIRCUIT VOLTAGE OF THE BATTERY. AS THE BATTERY VOLTAGE GOES HIGHER (TOWARDS THE 2.3VOLT/CELL LEVEL), THE BATTERY CURRENT WANTS TO INCREASE.

IN THE EVENT OF A SHORTED CELL OR A SEVERELY DISCHARGED BATTERY, THE POWER SUPPLY WILL GO INTO A “CURRENT LIMIT” MODE AND THEREFORE STARVE THE BATTERY, BUT NOT THE CRITICAL LOAD.