Geartooth speed sensors and limit switches meet UL specification 325 Class I and II


Geartooth speed sensors and limit switches meet UL specification 325 Class I and II Safety is a prime consideration when specifying operators for both commercial and domestic garage doors, as clearly such doors are extremely heavy and have the potential to cause significant injury if components fail to limit the speed and travel of their movement. The UL specification that relates to garage door operators, UL325, now covers operators for both domestic garage doors (Class I regulations) and commercial garage doors (Class II regulations).

In both instances, the primary sensing devices used must satisfy regulations for inherent entrapment sensing which includes current sensing, zero speed or equivalent, meaning a maximum door travel speed of one foot per second.

Secondary devices are also required as backup and must have provision for - or be supplied with - a photoelectric sensor, a contact sensor or an actuating device requiring continuous pressure to maintain the opening or closing motion of the door. ZF Electronics designs and manufactures a range of Cherry brand switches and sensors which meet or exceed UL standards, are economical and yet robust enough to suit demanding environments and withstand repeated operation.

ZF Electronics' new Cherry GS1001/GS1002 and GS1012 series geartooth speed sensors are well suited to OEM requirements for garage door operators, as they are immune to rotational alignment and accurately sense the movement of ferrous geartooth targets down to near zero speed.

10-bit dynamic threshold detection means that these sensors automatically adjust their magnetic range and compensate for changes in target geometry, as well as being immune to target run out. GS1001-1002 Hall-effect geartooth speed sensors are circuit-protected and available with an adjustable stainless steel housing.

The Cherry GS1012 series flange-mount geartooth speed sensors are resistant to fuels, solvents and lubricants, so are particularly suited to commercial doors for harsh commercial environments, such as automotive engineering workshops. Rated to 150ÂșC, the gear sensor's sealed design exceeds IEC60529 IP67 for fluid immersion.

Full specifications on the GS1001-1002 series and GS1012 series geartooth sensors and individual product datasheets can be downloaded from: http://www.cherry.co.uk/english/switches_controls/Geartooth.htm

Visit Cherry at www.cherry.co.uk

 

As featured in TES - The Electronic Supplier E-Zine, 2010 Vol 6, www.the-electronic-supplier.com/ezine/