GMT Fuses

When a GMT fuse trips, a fuse element burns out allowing the indicator to connect DC power to the alarm contact. This turns on the fuse alarm LED on the fuse panel indicating the affected group and the Controller reports a fuse alarm. Each Controller fuse alarm combines alarms from 4 individual fuses:

Fuse F1 to F4: Controller Fuse Alarm 1

Fuse F5 to F8: Controller Fuse Alarm 2

Fuse F9 to F12: Controller Fuse Alarm 3

Fuse F13 to F16: Controller Fuse Alarm 4.

To disconnect a load attached to a GMT fuse, pull the fuse straight out of the fuse holder base.

4.4.Battery Management

Battery Charging

Battery charging is integrated into the dc power system to support the primary function of providing power to the load. Accurate measurement of battery parameters such as voltage, current and temperature are used to maintain and protect the batteries attached to the power plant.

Charging the battery at the correct rate reduces battery heating, increases the charge returned to the battery and prevents excess hydrogen generation or, in the case of Valve Regulated Lead Acid (VRLA) batteries, possible thermal runaway. The Magnum VS operates as a current limited constant voltage battery charger. The current limit value is set by the controller’s Battery Maximum Recharge Current parameter and is normally based on the size of the battery plant in ampere-hours.

Consult the battery manufacturer for the recommended maximum charging current. This is frequently expressed as a percentage of the battery's 20-hour ampere-hour capacity rating, commonly abbreviated as "C". For example, the maximum recharge current in amperes may be expressed as 0.2C, 20% C or C/5, all of which are equivalent. If the battery used has a capacity of 120 Ah, then the 0.2 C max current is 24 amperes. Manufacturers typically specify max recharge current between 0.1C to 0.3C (C/10 to C/3). Avoid high recharge rates that may induce elevated battery temperatures that can lead to thermal runaway. A 0.1C max recharge current is generally a conservative value that will result in a 90-95% recharge in 12-15 hours, depending on the initial depth of discharge. In this case charging current will begin to taper (reduce) from the current limited value after 3.5 - 7 hours.

Typically four 12-volt batteries are connected in series to form a battery string. The ampere-hour rating for one 12- volt battery will equal the Ah rating of the string. For multiple parallel strings, add the Ah rating of each string together to get the total Ah rating.

Magnum VS –48 Vdc User Manual

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American Power Conversion VS 50, VS 100 user manual Battery Management, GMT Fuses, Battery Charging
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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.
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