SCR power controllers
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heaters sensors controllers Better Thermal Solutions.. Jaster

Watlow® Silicon Controlled Rectifiers (SCRs): Make Your Thermal System All That It Can Be Minimizing temperature extremes results in less expansion and contraction of the heater element and extends heater life. By reducing the time base, on-to-on cycle time, the resistance heater can provide a smooth, even output. SCR: Controlling Thermal Excursions Through Reduced Time Base By comparison, solid state relays (SSRs) are able to operate on a one-second time base. This reduces the temperature difference between the overshoot and droop points and increases the life of the heater. The power...

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Thermal Excursion: The Deadliest Disease for Electric Heating Elements A temperature controller with an onoff control mode has a characteristic over- and undershoot as it oscillates about set point. The greater the thermal excursion between the over- and undershoot temperatures, the greater the thermal expansion and contraction of the element wire in the electric heater. This makes the wire more brittle and causes it to breathe and oxidize. The work hardening of the element causes breakage and heater failure. Using SCR controllers in your process eliminates overshoot and droop to ensure...

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Relationship: Heater Life vs. Time Base Hours* To Failure Over 7000 Hours and Still Cycling Tests results show Watlow SCRs provide up to 20 times longer heater life. msec. msec. Time Base Seconds *(The hours represented on this chart are the result of an accelerated life test and are for comparison purposes only.) Watlow SCRs: Dramatically Increase Heater Life As time-base cycling rates increase past one second, they become more damaging to the heater element. Faster cycling does not cause as much expansion or contraction of the element wire. SCRs, cycling at less than one second, stabilize...

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SCR Power Controller Products Quick Selection Chart Product Firing Mode POWER SERIES Burst firing • Contactor • Variable time base Current 65 to 250A See rating curve Burst firing • Contactor • Variable time base VAC or VDC Burst firing Contactor input Microprocessor design with heater diagnostics and communications. Quick delivery. Resistance element, Nichrome®-Watlow Modular design incorporating plug-in cards for burst firing; contactor, variable time base, or phase-angle firing options. Quick delivery. Resistance element, Nichrome®-Watlow Burst firing on 1- and 3-phase. Shorted SCR and...

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Find out more about Watlow and how we can provide thermal solutions for your company: Phone: 1 . 800 . WATLOW2 E-mail: info@watlow.com Web site: www.watlow.com Watlow Products and Technical About Watlow Support Delivered Worldwide Watlow designs and manufactures industrial heaters, temperature North American Technical Support & Sales Ofces North America Asian Technical Support & Sales Ofces Australia assemblies – all of the components of a thermal system. Designing and manufacturing the complete thermal system allows Watlow to recommend, develop and deliver the optimum thermal solution for...

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