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Publication No: US-HX-IOM-002 - March 2004
www.enersysinc.com
Torque
The maximum torque load of intercell connector bolts is 6.8 to 10 Nm
(60 to 88 lb. in) for M6 screw. A loose connector can cause problems in
charger adjustment, erratic battery performance, possible damage to the
battery and/or personal injury. Finally, install the connector covers (optional).
CELLS IN PARALLEL STRINGS
When using constant voltage chargers, ensure that the connections
between the charger and the end of each string within the battery have the
same electrical resistance. Parallel strings must be limited to five strings.
CHARGING
Float Voltage
The float/charge voltage is 2.26 V per cell at 77°F (25°C).
When the average ambient temperature deviates more than ± 9°F (5°C)
from the reference, it is necessary to adjust the float voltage as follows :
2.37 to 2.38 Vpc at 32°F, (0°C)
2.30 to 2.33 Vpc at 50°F, (10°C)
2.27 to 2.30 Vpc at 68°F, (20°C)
2.24 to 2.27 Vpc at 77°F, (25°C)
(reference T°C)
2.23 to 2.26 Vpc at 86°F, (30°C)
2.21 to 2.24 Vpc at 95°F, (35°C)
Due to the phenomena of gas recombination a difference of ± 2% (earlier in
float life ± 5% is common) for an individual cell voltage can be observed.
However the total voltage of the battery shall be within the limits stated
above.
Charging Current
The charging current is self limiting.
Fast Recharge
Occasionally (4 or 5 times a year) the battery may be recharged at 2.40 V per
cell with a current limited to the values listed in the Table 2. Fast charging
should be stopped after approx. 10 or 15 hour.
Ripple Current
Unacceptable levels of ripple current from the charger or the load can cause
permanent damage and a reduction in service life. It is recommended to
limit the continuous ripple current to the values of the Table 2 (in amperes).
State of Charge
The battery state of charge can be determined approximately by measuring
the open circuit voltage after the battery has been at rest for a minimum of
24 hours at 77°F (25°C).
DISCHARGING
End of Discharge Voltage
The end of discharge voltage must be limited to 1.60 V per cell.
A protecting system shall have to be installed to prevent deep discharge.
Discharged Cells
DataSafe HX batteries must not be left in a discharged condition after
supplying the load, but must be immediately returned to float recharge
mode.
Failure to observe these conditions may result in greatly reduced service life
and unreliability.
Accidental Deep Discharge
When the battery is completely discharged, the sulfuric acid is completely
absorbed and the remaining electrolyte consists only of water.
At this point, the sulfation of the plates is at its maximum, considerably
increasing the cell’s internal resistance.
- Important notice :
this type of deep discharge will provoke a premature
deterioration of the battery and a noticeable effect on life expectancy.
The effect of temperature
- on capacity
Correction factor of the capacity, according to temperature.
MAINTENANCE/CHECKS
DataSafe HX are maintenance free, sealed, lead acid batteries and need no
water addition.
The containers and lids shall be kept dry and free from dust. Cleaning must
be done only with a damp cotton cloth. Check monthly that total voltage at
battery terminals is (N x 2.24 to 2.27 V) for a temperature of 77°F (25°C).
(N being the number of cells in the battery).
Every 12 months, read and record the following:
Individual cell or unit voltages (volts)
Cell-to-cell connection resistance (ohms)
Terminal connection resistance (ohms)
Ambient temperature in the immediate battery environment
Keep a logbook to record values, power outages, discharge tests, etc.
An autonomy check can be carried out once or twice a year.
The above record taking is the absolute minimum to protect the warranty.
This data will be required for any warranty claim made on the battery.
RECOMMENDED CURRENT LIMIT VALUES WHEN
RECHARGING WITH CONSTANT VOLTAGE
RECHARGING METHOD
41°F, (5°C)
0.84
50°F, (10°C)
0.88
59°F, (15°C)
0.93
68°F, (20°C)
0.97
77°F, (25°C)
1.00
86°F, (30°C)
1.03
95°F, (35°C)
1.05
104°, (40°C)
1.07
Time of discharge
1 min to 60 mins
HX205
4.0
2.0
HX300
7.0
3.5
HX330
7.0
3.5
HX400
8.5
4.25
HX500
10.0
5.0
Type
Maximum charging
Max recommended rms
current (A)
value of the alternating
component (A)
Table 1
Table 2
State of charge
Voltage
100%
2.13 to 2.14 V/Cell
80%
2.09 to 2.11 V/Cell
60%
2.06 to 2.08 V/Cell
40%
2.02 to 2.04 V/Cell
20%
1.97 to 2.00 V/Cell
