capacitive device designed to initiate control
operations when a metal antenna is touched.
Antenna size and shape are determined by the application; an antenna may be up to 200 feet long or have an area of 15 square feet. Adequate sensitivity is provided to insure operation if the antenna is covered with paint, oil, or dirt or if thin gloves are worn.
Principles of Operation
The PC200 Touch Switch system is comprised of: a control unit, and a customer-supplied antenna.
The Touch Switch is an electronic device which is sensitive to changes in capacitance. When a person's body or a grounded metal object comes into contact with the antenna, a large change in capacitance results. Because it is capacitance, rather than electrical conductivity which is sensed, it isn't necessary to make what is commonly thought of as an electrical connection with the antenna; therefore, the antenna may be covered with paint, electrical tape, or other thin insulating material and still function normally.
When sufficient external capacitance change is introduced, the internal signal voltage drops below a preset threshold level and causes the control relay to open. For speed purposes, the normal state of the relay is energized (closed contacts). This provides a faster response time and security against relay failure - if the relay coil fails, the control contacts open.
The Touch Switch is designed to tune a wide range of antenna capacity (0-1000pF). This gives the user plenty of latitude in application and doesn't confine the touch surface to a small size or area. This makes the application possibilities for the Touch Switch virtually limitless.
|Conveyor Line Control||Level Detector||Machine Stop|
|Parts Detector||Limit Switch|
Easily Installed by Plant Electrician
Complete Access and Visibility at Point of Operation
Antennas are Application-Specific and can be Any Shape or Configuration
Antennas Can Be Metal Rod, Pipe, Tubing or Flat Stock, Mounted on Insulators
Low Cost Permits Installation at Each Location Where a Control Switch Need Exists