SPECTEC has three principal types of zero speed sensors:
- Hall effect magnetic sensor is activated by a magnetic target/li>
- Hall effect gear tooth sensor is biased by an internal magnetic to be activated by a ferrous target, and
- Hall effect quadrature sensors for detecting motion and direction
- Intrinsically Safe Hall effect sensors for use in various locations.
The Hall effect technology fulfills a wide array of applications due to a Hall effect sensor's ability to detect zero speed and direction change and produce a digital output that is read by computers, motion control devices, position monitors and digital to analog converters. SPECTEC's zero speed Hall effect sensors are used in industrial applications to determine shaft or gear speed or direction by detecting fluctuations in the magnetic field. SPECTEC's Intrinsically Safe Hall effect sensors are certified by Factory Mutual.
Magnetic target Hall effect sensors are designed to switch in the presence of a magnetic field of 50 Gauss minimum. The H type Hall effect sensor meets a wide array of applications due to its ability to detect the difference in a magnet's north or south pole disposition.
Both uni-polar (activated by either north or south pole magnets) and bi-polar (alternating north-south pole activation) are offered. In addition, an omni-polar model (HO type) is available which responds equally to a north or south pole field and converts it to a digital pulse.
SPECTEC's HF and HHF type Hall effect sensors are engineered with an internal magnet to switch in the presence of ferrous targets such as gear teeth and blade tips down to absolute zero speed. The gear-type Hall effect sensor can detect fluctuations in the magnetic field and can also be configured to detect the either the presence or absence of a ferro-magnetic target (i.e. a gear tooth).
The gear position Hall effect sensor has the ability to sense a ferrous target while applying zero drag on the target wheel with a sensitivity that detects gear teeth as small as 0.10" wide and 0.10" deep. Air gaps of up to 1/8 inch are possible, depending on mass of target (size of gear).
Zero Speed Sensors - Quadrature Sensor (Directional)
The HHF type quadrature Hall effect sensor has the ability to detect the direction a ferrous target is traveling while applying zero drag on the target wheel. This quadrature Hall effect sensor has a sensitivity that detects gear teeth as small as 0.10" wide and 0.10" deep. Air gaps of up to 0.125" inch are possible, depending on the size of the target gear.
SPECTEC's line of Hall effect sensors include intrinsically safe, single output, dual output, additional temperature output, hermetically sealed, sanitary and conduit mount.
Standard output (NPN) is provided by a 2.2 K ohm internal resistor to a collector which can sink 25mA. In addition, PNP and open collector types are available in order to serve all logic needs. The H and HF zero speed Hall effect sensors are used in speed applications and digital devices which switch from logic state 0 to logic 1 in the presence of a magnetic field of 50 gauss (H type) and 5 - 10 gauss (HF type).
Zero Speed Sensor Applications:
Hall effect sensor applications such as fine gears, detection of very low to zero speed and the change in target direction. Hall effect sensors are used as vehicle speed sensors, wheel speed sensors, in ABS brake systems and as camshaft sensors.