orderly shutdown of industrial PCs and other devices. They have a long life and can provide up to 20 kilowatt seconds (kWs) of backup power. For example, Siemens’ model 6EP19332EC41 capacitor energy storage unit can provide up to 2.5 kWs of backup power. Lead-acid and various lithium- ion chemistries can be useful for longer backup power needs, which take up to several hours for critical communications or process operations (Figure 6). Basic DC UPS battery modules with up to 38 Ah of storage are available. Multiple battery modules can be used to provide backup times of several hours. The 6EP19356MD31 DC UPS battery
module from Siemens uses maintenance-free sealed lead-acid batteries to provide up to 15 A with a storage capacity of 2.5 Ah. Conclusion VSDs/VFDs are often considered to be the workhorses of industrial automation. However, a comprehensive industrial automation architecture requires more, including servo drives, motors, and soft start-stop units. Industrial automation system designers also have numerous DC power architectures to select from when optimizing uptime and reliability.
Uninterruptible power Redundant power can be useful, but it’s not enough for critical applications. When traceability and data collection are mandatory, safety is a concern,
or uninterrupted operation is required, a UPS like the
6EP41363AB002AY0 SITOP UPS from Siemens will be needed. This UPS provides a 24 V DC output and can deliver up to 20 A. One of the key questions when selecting a UPS is the energy storage technology. Ultracapacitors, also called double- layer capacitors, are suited for short-term backup power needs like saving process data and
we get technical
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