NPX-25T EnerSys, NPX-25T Datasheet - Page 13
![DATASAFE NPX LEAD ACID BATT 12V](/photos/27/82/278230/npx-25t_sml.jpg)
NPX-25T
Manufacturer Part Number
NPX-25T
Description
DATASAFE NPX LEAD ACID BATT 12V
Manufacturer
EnerSys
Specifications of NPX-25T
Voltage - Rated
12V
Rechargeability
Yes
Lead Free Status / RoHS Status
Contains lead / RoHS compliant by exemption
Size / Dimension
-
Termination Style
-
Capacity
-
Other names
Q5397175
www.enersys.com
Figure 16. Cyclic Service Life in Relation to Depth of Discharge
Remote site, or other outdoor applications for solar systems is
commonplace. When designing a solar system for this class
of application, a great deal of consideration must be given to
environmental conditions. For example, enclosures which
may be used to house batteries and other equipment may be
subject to extremely high internal temperatures when
exposed to direct sunlight. Under those conditions, insulating
the enclosure and/or treating the surface of the enclosure with
a highly reflective, heat resistive material is recommended.In
general, when designing a solar system, consultation with the
solar panel manufacturer and battery manufacturer is
recommended
■
There are a number of factors that will effect the length
of cyclic service of a battery. The most significant are
ambient operating temperature, discharge rate, depth of
discharge, and the manner in which the battery is recharged.
Generally speaking, the most important factor is depth of
discharge. Figure 16 illustrates the effects of depth of
discharge on cyclic life.
The relationship between the number of cycles which can be
Figure 15. Block Diagram of a Solar System
Expected Service Life of Genesis
NP Batteries
Cyclic Service Life
(AH%)
120
100
40
80
60
20
0
Genesis NP Series
TESTING CONDITIONS: DISCHARGE CURRENT: 0.17C AMP. (F.V. 1.7V/CELL)
200
.
100% D.O.D.
NUMBER OF CYCLES (CYCLES)
400
CHARGING CURRENT: 0.09C AMP.
CHARGING VOLUME: 125% OF DISCHARGED CAPACITY
AMBIENT TEMPERATURE: 20°C TO 25°C (68°F TO 77°F)
50% D.O.D.
600
800
30% DEPTH OF DISCHARGE
1000
1200
1400
expected, and the depth of discharge is readily apparent. In
relation to a specified discharge rate, if the application
requires a longer cyclic life than is obtainable by selecting the
battery capacity according common practice, select a battery
with larger capacity. Thus, at the specified discharge rate
over the specified time, the depth of discharge will be
shallower and cyclic service life will be longer.
■
Genesis NP batteries are designed to operate in standby
(float) service for approximately 5 years, based upon a normal
service condition in which float charge voltage is maintained
between 2.25 and 2.30 volts per cell in an ambient
temperature of approximately 25
Figure 17 shows the float service life characteristics of
Genesis NP batteries when discharged once every three (3)
months to 100% depth of discharge.
In normal float service, where charging voltage is maintained
2.25 to 2.30 volts per cell, the gases generated inside and
Genesis NP battery are continually recombined, and return to
the water content of the electrolyte. Therefore, electrical
capacity is not lost due to “drying up” of the electrolyte.
Actually, through the gradual and very slow corrosion of the
electrodes, the battery will eventually lose capacity and come
to the end of service life. It should be noted that the corrosive
process will be accelerated by high ambient operating
temperatures and/or high charging voltage. When designing
a float service system, always consider the following:
LENGTH OF SERVICE LIFE WILL BE DIRECTLY
EFFECTED BY THE NUMBER OF DISCHARGE CYCLES,
DEPTH OF DISCHARGE, AMBIENT TEMPERATURE, AND
CHARGING VOLTAGE.
Figure 17. Float Service Life
Float Service Life
TESTING CONDITIONS: FLOATING VOLTAGE: 2.25 to 2.30V/CELL
Publication No: US-NP-AM-002 • June 2006
AMBIENT TEMPERATURE: 20ºC TO 22ºC (68ºF TO 72ºF)
0
C (77
0
F).
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