LEM's Sentinel 3+ is a battery-monitoring transducer that measures
the voltage, temperature and impedance of cells and complete batteries in
uninterruptible power supply (UPS) installations of all sizes up to mega-watt
back-up power supplies for data centers and hospitals. Sentinel 3+ reports its
measurements - on valve-regulated lead-acid (VRLA), gel or flooded stationary
batteries - to supervisory systems over a dedicated communications bus, and
offers a unique capability to assess the true state-of-health of UPS batteries
while they are in service. Sentinel 3+ gives complete confidence that battery
arrays will deliver their rated power when called on to do so, and identifies
weak and failing cells without the need to remove them from service for cycling
Technology developments such
as the availability of fast insulated-gate bipolar transistors (IGBTs) reduce
costs by eliminating transformers from their circuit configurations. The
battery packs that the Sentinel product monitors are operated in a floating
voltage mode: the battery is subjected to higher ripple currents, and the
monitoring circuitry must handle high common-mode voltages, with superimposed
high-amplitude, fast transients.
LEM's Sentinel 3+ has upgraded
algorithms to address more challenging measurement environments and improved EMC
immunity and enhanced robustness. Sentinel 3+ delivers voltage measurements
over a range of 0.9 to 16 V with an accuracy of +/-0.5 percent; impedance
measurement from 0.05 to 250 mO with repeatability of +/-2 percent.
Sentinel 3+ features Common Mode Transient Immunity up to 20 kV/µsec with a
common-mode voltage level of +/-600 V, and a transient repetition rate of 20
Samsung's Galaxy line of smartphones used to fare quite well in the repairability department, but last year's flagship S5 model took a tumble, scoring a meh-inducing 5/10. Will the newly redesigned S6 lead us back into star-studded territory, or will we sink further into the depths of a repairability black hole?
In 2003, the world contained just over 500 million Internet-connected devices. By 2010, this figure had risen to 12.5 billion connected objects, almost six devices per individual with access to the Internet. Now, as we move into 2015, the number of connected 'things' is expected to reach 25 billion, ultimately edging toward 50 billion by the end of the decade.
NASA engineer Brian Trease studied abroad in Japan as a high school student and used to fold fast-food wrappers into cranes using origami techniques he learned in library books. Inspired by this, he began to imagine that origami could be applied to building spacecraft components, particularly solar panels that could one day send solar power from space to be used on earth.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.