Three-phase power supplies with current limiting
These three-phase power supplies include constant current mode, which limits output current to typically 110% of rated current with a simultaneously lowered voltage output in an overload condition.
The 787 PRO series three-phase power supplies come with freemonitoring and configuration software and feature PowerBoost and TopBoostfunctions, line monitor capability and 93% efficiency. The six-model line ofthree-phase power supplies offers a wide input voltage range; a 24 Vdc output;and 10 A-, 20 A- or 40 A-rated nominal output, depending on model.
In short-circuit conditions, TopBoost provides 60 A ofadditional 50 ms reserve for tripping of miniature circuit breakers. PowerBoostoffers up to 200% of rated current for up to four seconds to assist power-up ofheavy loads such as motors. All models include constant current mode, whichlimits output current to typically 110% of rated current with a simultaneouslylowered voltage output in an overload following PowerBoost. Select modelsprovide adjustable output voltage characteristics: a time-limited constantcurrent and permanently reduced current (e.g., Fuse Mode or Mixed Mode).
The line monitor (on select models) incorporates anLCD/keypad and an RS-232 interface with free software for monitoring andconfiguring signal outputs and overcurrent behavior. Monitoring from the LCDand software via RS232 interface eliminates components such as volt/amp meters,phase monitoring devices and operational hour meters.
LEDs on the power supply indicate errors. An optional LCDscreen provides current, voltage output and line monitoring information. Onselect models, four active signal outputs may be used for function monitoringand data transfer to higher-level systems. All units employ pluggable CAGECLAMP electrical connectors for fast, easy and maintenance-free terminations.PRO Power Supplies carry UL508 and UL60950 and use a rugged metal housing thatmay be DIN-rail mounted horizontally or vertically.
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After almost a decade of uncertainty, the confidence of plant floor managers is soaring. Even with a number of challenges and while implementing new technologies, there is a renewed sense of optimism among plant managers about their business and their future.
The respondents to the 2014 Plant Engineering Salary Survey come from throughout the U.S. and serve a variety of industries, but they are uniform in their optimism about manufacturing. This year’s survey found 79% consider manufacturing a secure career. That’s up from 75% in 2013 and significantly higher than the 63% figure when Plant Engineering first started asking that question a decade ago.