24 | SAMLEX AMERICA INC.
SECTION 7 |
General Information on Lead Acid
Batteries
4UBUFPG%JTDIBSHF 4UBUFPG$IBSHFBUWFSZIJHI$SBUFEJTDIBSHF
DVSSFOUPG$"NQT
4UBUFPG%JTDIBSHF 4UBUFPG$IBSHFBUIJHI$3BUFEJTDIBSHF
current of C/5 Amps.
EJTDIBSHFE 4UBUFPGDIBSHFBUMPXFS$SBUF%JTDIBSHFDVSSFOUPG$"NQT
*UJTTFFOUIBUBU%$JOQVUWPMUBHFPG77UIFCBUUFSZJTDPNQMFUFMZEJTDIBSHFEGPS
C-rate discharge current of C/5 and lower.
In view of the above, it may be seen that a fi xed Low DC Input Voltage Alarm is not useful.
Temperature of the battery further complicates the situation. All the above analysis is based
POCBUUFSZFMFDUSPMZUFUFNQFSBUVSFPG¡'5IFCBUUFSZDBQBDJUZWBSJFTXJUIUFNQFSBUVSF
Battery capacity is also a function of age and charging history. Older batteries have lower
capacity because of shedding of active materials, sulfation, corrosion, increasing number of
DIBSHFEJTDIBSHFDZDMFTFUD)FODFUIF4UBUFPG%JTDIBSHFPGBCBUUFSZVOEFSMPBEDBOOPU
CFFTUJNBUFEBDDVSBUFMZ)PXFWFSUIFMPX%$JOQVUWPMUBHFBMBSNBOETIVUEPXOGVODUJPOT
BSFEFTJHOFEUPQSPUFDUUIFJOWFSUFSGSPNFYDFTTJWFDVSSFOUESBXOBUUIFMPXFSWPMUBHF
7.13 USE OF EXTERNAL PROGRAMMABLE LOW VOLTAGE DISCONNECTS
5IFBCPWFBNCJHVJUZDBOCFSFNPWFECZVTJOHBOFYUFSOBMQSPHSBNNBCMF-PX7PMUBHF
%JTDPOOFDUXIFSFNPSFFYBDUWPMUBHFUISFTIPMEDBOCFTFUUPEJTDPOOFDUUIFCBUUFSZ
based on the actual application requirements. Please consider using the following
1SPHSBNNBCMF-PX#BUUFSZ$VUPGGi#BUUFSZ(VBSEw.PEFMTNBOVGBDUVSFECZ4BNMFY
"NFSJDB*ODXXXTBNMFYBNFSJDBDPN
#( "o'PSVQUP87JOWFSUFSPS87JOWFSUFS
#( "'PSVQUP87JOWFSUFSPS87JOWFSUFS
#( "'PSVQUP87JOWFSUFSPS87JOWFSUFS
7.14 DEPTH OF DISCHARGE OF BATTERY AND BATTERY LIFE
The more deeply a battery is discharged on each cycle, the shorter the battery life. Using
NPSFCBUUFSJFTUIBOUIFNJOJNVNSFRVJSFEXJMMSFTVMUJOMPOHFSMJGFGPSUIFCBUUFSZCBOL
"UZQJDBMDZDMFMJGFDIBSUJTHJWFOJOUIF5BCMF
TABLE 7.6: TYPICAL CYCLE LIFE CHART
Depth of Discharge
% of Ah Capacity
Cycle Life of Group
27 /31
Cycle Life of Group
8D
Cycle Life of Group
GC2
10
1000
1500
50
480
1100
80
200
100
150
225
550
NOTE:
It is recommended that the depth of discharge should be limited to 50%.