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SMOKE SPILL INDUCTION MOTORS

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STANDARDS AS 1668, AS 1359, BS 7349, BS 4999, BS 5000, IEC 34, IEC 72. GENERAL Western Electric Smoke Spill motors are designed to meet the requirements of Bitish and Australian Standards. AS 1668. 1 states that the objectives of Smoke Control are:         a) to vent smoke from the fir-affected compartment: and         b) to reduce the spread of smoke to fire isolated exits and other compartments.   In general Smoke Spimm motors are required to continue to operate driving extraction fans in a building, in the case of a fire. Usually these motors operate air circulation fans as part of the normal operation of the building, however if a fire occurs they must continue to operate for a period of time to extract smoke and\or dangerous fumes from the building and allow rescue services some assistance in rescuing any occupants still in the building. it is expected that hte fumes being extracted will be at high temperatures, well above normal ambients
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HAZARDOUS AREAS - Comparisons Between Standards

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The following tables and comments are an attempt to cross reference between different National standards for Hazardous Location Definitions. We note that there is a world wide trend towards IEC standards in the electrical industry and that even the American manufacturers are gearing up to produce products to IEC standards in IEC metric dimensions. COMPARISON OF ZONES FOR ELECTRICAL EQUIPMENT IEC/CENELEC/U.K. GERMANY/JAPAN U.S.A. ZONE 0 DIVISION 1 ZONE 1 DIVISION 1 ZONE 2 DIVISION 2 COMPARISON OF CLASS II CLASSIFICATIONS - DUSTS B.S.6467 & A.S. 2236 -CLASS II U.S.A.-CLASS II DIP - NO SUB - GROUP GROUP E - METAL DUSTS GROUP F - COAL DUSTS GROUP G - GRAIN DUSTS COMPARISON OF GAS GROUPINGS FOR ELECTRICAL EQUIPMENT IEC CENELEC AUSTRALIA U.KBS4683 GERMANY & JAPAN VDEO171 RIIS-TR-TR-79-1 U.S.A. NATIONAL ELECTRIC CODE Representative Gases II IIA II IIA 1 D Propane IIB IIB 2 C Ethylene IIB IIC 3n 3a B Hydrogen IIB 3b
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Fuse Construction and Operation

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The typical fuse consists of an element which is surrounded by a filler and enclosed by the fuse body. The element is welded or soldered to the fuse contacts (blades or ferrules). The element is a calibrated conductor. Its configuration, its mass, and the materials employed are selected to achieve the desired electrical and thermal characteristics. The element provides the current path through the fuse. It generates heat at a rate that is dependent upon its resistance and the load current. Mersen (Gould Ferraz Shawmut) Fuse Construction The heat generated by the element is absorbed by the filler and passed through the fuse body to the surrounding air. A filler such as quartz sand provides effective heat transfer and allows for the small element cross-section typical in modern fuses. The effective heat transfer allows the fuse to carry harmless overloads. The small element cross section melts quickly under short circuit conditions. The filler also aids fuse performance by abs
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8 Most Common Level Sensing Methods

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Level sensors have been a part of manufacturing processes for several decades, in industries as diverse as food and beverage, semiconductors, and pharmaceutical. However, equipment manufacturers and users may be surprised at both the breadth and sophistication of level sensing alternatives currently available.   Measurements and actions that used to require large, mechanical, and expensive devices can now be performed using advanced, highly versatile technologies that are also durable, precise, and easy to implement. What’s more, a variety of level sensing technology options work well with what have traditionally been challenging substances such as sticky fluids (e.g., molasses, glue, ink) and foam (beer, pulp, hydraulic fluid, soap).   Some users may question the need for such technology - or any level sensing device, for that matter - arguing that existing, “tried-and-true” methods are well-suited for the basic nature of most level sensing tasks. But today’s manufacturing env
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WAGO e!DISPLAY Web Panels

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For visualization tasks with CODESYS V2 and V3: WAGO’s attractive e! DISPLAY 7300T HMI Panels help you reinforce the quality of your machinery and equipment with a refined design. HMI panels are the perfect finishing touch for machines or systems, and the look and feel of these panels positively impacts purchase decisions. WAGO offers aesthetically pleasing HMIs that leave a lasting impression shile significantly increasing the value and improving the image of your machine or system: The e! DISPLAY 7300T Web Panel is available in 4.3″, 5.7″, 7.0″ and 10.1″ display sizes. Your benefits with e! DISPLAY Web Panels: High-performance HMI display with a resistive touch screen for Web-based visualization Available in four screen sizes (4.3″, 5.7″, 7.0″ and 10.1″) Modern visualization via CODESYS V2 and e! COCKPIT (based on CODESYS V3) Support new technologies such as HTML5 High-performance solutions when combined with PFC200 and PFC100 Controllers What Makes e! DISP
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WAGO PFC100 Controllers

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A fast CPU, flanked by a large amount of data processing, a runtime system with e! COCKPIT , Linux ® and multiple interfaces, as well as cybersecurity via SSL/TLS encryption, VPN and a firewall: This is what the PFC100 Controller offers! Diverse outputs in a compact housing! With the PFC100 Controller, WAGO offers an excellently equipped controller at a compelling cost-benefit ratio: This PLC combines the best from both the Linux ® and CODESYS worlds into one device. This compact controller (PLC) offers a flexible solution not only for industrial process applications, but also for mechanical engineering applications. Your benefits with WAGO PFC100 Controller includes: Cost-effective configuration via e! COCKPIT Engineering Software Cybersecurity via SSL/TLS encryption, VPN and a firewall Integrated Webserver microSD card Web visualization in HTML5 Linux ® real-time operating system What Makes the PFC100 Controller Successful? Advanced, Economical and Ef
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Electromechanical Relays (EMRs) vs. Solid State Relays Comparison (SSRs)

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Electromechanical Relays (EMR) Pros (Advantages) Lower initial cost compared to solid state relays. Provides complete electrical isolation. Tolerates high current & voltage transients. Insensitive to electromagnetic interference (EMI) / radio frequency interference (RFI). Higher open resistance (air gap). Lower closed resistance. Available with many poles/circuits (up to 8 or more). Many different circuit configurations available. Multiple packaging & feature options. Most typical failure mode is open. Electromechanical Relays (EMR) Cons (Disadvantages) Higher control (coil) power consumption. Contact arcing can cause pitting & eventual open/short failure. Contacts can be affected by corrosion, oxidation or contamination. Contact bounce possible due to shock & vibration. Generates electromagnetic interference (EMI) / radio frequency interference (RFI). Can be orientation sensitive. Can be affected by external magnetic fields. Subject to mechanic
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