Battery Protection

An external disconnect should be mounted at the battery string to protect the system from the high energy stored in the battery if a short occurs. The battery LVD will not be energized until a battery string is installed with the proper polarity and the battery disconnect switch is turned on. The battery connections are to be used for the battery only. Do not attach loads to the battery connections or erroneous battery current will be reported. The controller reports Battery high and low voltage alarms and LVD alarms.

Battery Temperature Monitoring

Battery temperature is monitored using a probe attached to the battery casing. The controller reports Battery high and low temperature alarms.

Battery Temperature Compensation

The Battery Float Voltage is set to the value recommended by the battery manufacturer in order to maintain correct battery charge at 25ºC. As temperature rises, electrochemical activity in a battery increases. Similarly, as temperature falls, electrochemical activity in a battery decreases. As temperature rises, charging voltage should be reduced to prevent overcharge and possible thermal runaway. As battery temperature falls, voltage is increased to prevent undercharge. The dc power system uses Battery Temperature compensation to change output voltage to compensate for temperature changes monitored at the battery temperature probe. This temperature compensation function is programmed into the controller using the compensation parameters settings. Default settings can be changed to values recommended by the particular battery manufacturer. The controller will not allow the system voltage to be adjusted beyond the range of –47 Vdc to –56.5 Vdc.

Battery Low Voltage Disconnect

In order to prevent damage to the battery due to deep discharge, the dc power system has hardware and software support for a battery Low Voltage Disconnect (LVD). When the battery voltage reaches the threshold set by the LVD 1 Trip Voltage setting during discharge, the dc power system will activate the LVD contactor to disconnect the battery from the system. The LVD will remain open until ac power is restored to the system and the bus voltage reaches the level defined by the LVD 1 Reset Voltage variable. The LVD control can be disabled on the LVD parameters screen in the controller.

NOTE: The LVD is normally energized and must be commanded to open. This assures that the LVD will remain closed even if the controller fails or is removed.

The LVD will not be energized until a battery string is installed with the correct polarity and the battery disconnect switch is turned on. This will prevent the battery from being hooked up backwards and damaging the rectifiers and/or the loads. Once the battery is connected correctly and the LVD is closed, the LVD will open only in low voltage situations. The battery connections are to be used for the battery only.

Counter Electro-Motive Force Module Connections

A connection is provided to connect a Counter Electro-Motive Force (CEMF) Module. A CEMF is a semiconductor device connected in series with a battery and used to reduce the voltage to loads that cannot tolerate the “normal” main cell voltage. The CEMF cells are automatically switched out of the circuit when the discharge voltage drops to a predetermined level and are automatically switched back into the circuit when the battery approaches its normal float value.

Magnum VS –48 Vdc User Manual

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American Power Conversion VS 100, VS 50 Battery Protection, Battery Temperature Monitoring, Battery Low Voltage Disconnect

VS 50, VS 100 specifications

American Power Conversion (APC), a brand under Schneider Electric, is renowned for its uninterruptible power supplies (UPS) and provides a range of solutions for both commercial and personal use. Among their various product lines, the APC Smart-UPS 1000VA (VS 1000) and Smart-UPS 500VA (VS 500) stand out due to their features, technologies, and specifications tailored to different operational needs.

The APC Smart-UPS 1000VA is designed for advanced power protection, capable of supporting servers, network equipment, and more demanding applications. It features a pure sine wave output, which is critical for sensitive electronics, ensuring devices receive a stable and clean power source even during outages. The VS 1000 is equipped with an extensive battery backup, offering up to 9 minutes of runtime at full load.

A notable technology employed in the Smart-UPS 1000 is the Automatic Voltage Regulation (AVR), which maintains output voltage stability by adjusting boost and trim in situations of under or over voltage. The unit has an LCD interface, providing real-time data regarding load capacity, runtime, and battery health, enabling users to easily monitor and manage performance. Additionally, with its compact design, the VS 1000 can fit into various settings, maximizing space efficiency.

In contrast, the APC Smart-UPS 500VA targets smaller operations, offering a more compact solution for basic power protection needs. Like its larger counterpart, it also provides pure sine wave output, ensuring the safe operation of connected equipment. The VS 500 is designed for less intensive applications, making it suitable for desktop computers, network devices, and home office setups.

The 500VA model supports shorter runtimes, typically around 3 to 6 minutes under full load but is ideal for situations where downtime needs to be minimized. The Smart-UPS 500VA features similar Automatic Voltage Regulation technology, maintaining voltage stability under fluctuating conditions. However, it comes with a more straightforward LCD display, providing essential information on power status and battery levels without overwhelming the user.

In summary, the APC Smart-UPS 1000VA and 500VA cater to different user requirements, with the VS 1000 offering robust features for larger setups and the VS 500 serving as a versatile option for home or small office use. Both models integrate essential technologies such as pure sine wave output and AVR, showcasing APC’s commitment to high-quality power solutions. Whether for commercial or personal use, these units demonstrate APC's ability to provide reliable power protection tailored to diverse needs.