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REPRESENTATIONS. Trademarks NEC and the NEC logo are registered trademarks of NEC Corporation. ALM is a registered trademark and EverSafe is a trademark of NEC Energy Solutions, Inc. A123 Systems and Nanophosphate are registered trademarks of A123 Systems, LLC. All other trademarks used herein are the property of their respective owners.
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ALM 12V7 s-Series battery’s circuitry. • Do not connect the ALM 12V7 s-Series to an inductive load such as a DC motor without the use of a motor controller. An “on-off” switch does not constitute a motor controller. Using the batteries directly with DC motors can permanently damage the battery.
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Chapter 3: Handling, Storage and Installation NOTE The ALM 12V7 s-Series is UL Recognized as a standalone battery only and has not been evaluated by UL (or any other regulatory agency) for series and/or parallel configuration. NEC Energy Solutions has successfully conducted noncertification testing witnessed by UL on multi- battery arrays in series/parallel configurations.
(15,240 meters). • ALM 12V7 s-Series batteries have been tested to 11.6 kPa 20 °C ±5 °C at 20 °C ±5 °C. Transport et Entreposage Lors du stockage ou du transport des batteries ALM 12V7 s-Séries, NEC Energy Solutions recommande la suite: •...
Current that exceeds this value will be interrupted by the battery’s protection circuitry. Although high ripple current at low frequencies (60Hz/120Hz) is not recommended, the ALM 12V7 s-Series battery will support average ripple current with peaks up to 53 amps without any adverse effects. As a comparative example, the maximum ripple current for a typical AGM (absorbent glass mat) 12 volt 7 Ah VRLA battery (@ 20hr rate) would be 7 Ah/20 hr or 0.35 amps.
The ALM 12V7 s-Series is designed to enter an Under Voltage Protection (UVP) state if any cell drops below 2 volts. In the UVP state, the ALM 12V7 s-Series battery will disconnect its terminals causing the output voltage to drop to 0 volts. Slight differences in the cells’ state of charges lead to differences between the cell voltages, especially at low states of charge.
ALM12V7 s-Series batteries are designed to enter an Over Voltage Protection (OVP) state if any cell rises above 4.1 volts. In the OVP state, the ALM 12V7 s-Series will disconnect its terminals and not accept further charge current. To exit the OVP state, apply a load to discharge to the battery.
For charge acceptance, do not exceed the limits specified. For the higher temperatures (and charging rates), exceeding these rates may result in engaging the ALM 12V7 s-Series protection circuitry. For lower temperatures, exceeding these rates will result in a shorter battery life.
(14.4 V), as shown in Equation Eq. 1 (Number of Series Connected ALM 12V7 s-Series Batteries) x (14.4V) = Max Charge Voltage, Battery System. Table 15 shows Recommended Float and Maximum Charge voltages.
12V7 s-Series User’s Guide Chapter 5: Operation and System Design Considerations Voltage drop in the ALM 12V7 s-Series is an inverse function of the ALM 12V7 s-Series battery’s internal temperature. As the internal temperature of the ALM 12V7 s-Series drops, the impedance rises leading to an increased voltage drop.
Balancing Over time, the ALM 12V7 s-Series cells diverge in both capacity and SOC. All ALM 12V7 s-Series batteries perform cell voltage balancing at high SOC values based on cell voltage to maximize the available capacity of the battery. The balancing circuit’s purpose is to drive all cells to the same voltage.
Storage temperatures above 25 °C accelerate the rate of self-discharge and reduce the shelf life. At 10% SOC, the ALM 12V7 s-Series battery has about 5% of usable energy, on average, before entering into an Under Voltage Protection (UVP) state as described in Over Discharge 406014-02EN, Rev.
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Under Voltage Protection UVP state there is a limited time that the battery can remain without being charged. If the ALM 12V7 s-Series battery is discharged to the UVP 5% SOC level, it has approximately 30 days in this state, at 25 °C, before reaching its lowest power mode called the Under Voltage Lock-Out (UVLO) state.