Passives
APEM Introduces Hall Effect Switches for the Most Rugged and Harsh Environments
APEM has introduced two new Hall effect switches, designed to work in the most rugged and harsh environments. The new IH series of switches are low maintenance, contact less, sealed pushbuttons that come in two versions: linear proportional output, and momentary switch. The switches are made of extremely durable materials, including switch bushings of Zamak, a robust family of alloys with a base metal of zinc and alloying elements of aluminum, magnesium and copper. Life expectancy for both versions is estimated at above 5 million cycles at least ten times more than the classic mechanical switch, which is rated for about 500,000 cycles.
The IH linear version is ideal for control valves or variable speed drives. Suitable applications include industrial controls, heavy duty equipment and other handling applications where operators need to control motion and speed. The linear version can also function as an additional axis for handgrip/joystick operations. It is designed to react to the pressure exerted on the switch; response is proportional to actuator travel. Hall effect technology ensures no-contact, low wear and tear for reliable, long life. Mechanical life for the linear version is estimated at 5 million cycles. The switches feature outputs ranging from 0.5 volts to 4.5 volts. The more the switch is pressed, the higher the output voltage.
One of the key features of the IH linear version is that it can be customized. The switch can be tuned to three different operating forces, soft, standard, and hard. Many other Hall effect switches work with a fixed 5-volt voltage, a drawback for customers that may want to use the switch in a vehicle with a 12- or 24-volt battery, for example. To use a 5-volt linear switch in those circumstances would require a regulator to adapt the switch from 12 or 24to 5 volts. Adding extra electronic components adds costs and connections, so the IH linear switch’s regulator options a particularly cost effective solution.
Linear output can also be customized. While the standard version of the switch has an output of 0.5 volts for 0 mm travel, this value can be changed upon customer request from 0 to 2 volts, to adapt to situations where the linear switch may be connected to another electrical circuit. The voltage for maximum travel can also be tuned.
In addition to its long life and ability to be customized, the IH linear version switch has also been tested and approved for electromagnetic compatibility (EMC), and is extremely robust to disturbances. EMC testing conducted in accordance with IEC/EN61000-4-3 showed 10V per meter extend to radiated fields in a frequency range of 80 Megahertz (Mhz) to 1000Mhz.
The IH linear version is sealed to IP67 according to IEC 60529 and is rated to operate in temperatures ranging from -40°C to +85°C. The switch’s total travel is 4 millimeters (mm), about .160-inches. It offers a compact sized case of 12mm (.472-inches) and a low behind-panel depth.
The IH momentary switch version is designed to withstand 5 million cycles and repetitive jogging. It is especially appropriate for applications where positioning the load is critical, including material handling, loaders, lifts, trucks, buckets and shovels and other applications requiring continuous operations. Remote controls in rugged or outdoor environments would be an excellent application for the IH switch version.
The dome-shaped actuator is available in eight colors, and features a spring return that provides tactile feedback that the switch has been activated. Separating the sealing membrane, the spring, and the tactile feedback elements inside the switch optimizes mechanical life by greatly reducing wear and tear.
The momentary switches are rated for 28 volts direct current (VDC) at a maximum of 50 milliampere (mA). Supply voltage ranges from 3.5VDC to 24VDC. In the off position, the IHS switch consumes 2.5mA to 5mA.
Similar to the linear version, the IH switch version is also sealed to IP67, rated to operate in temperatures ranging from -40°C to +85°C, and offers a compact size and a low behind panel depth. The switch’s total travel is 1.70mm (.070-inches). It has an operating force of 6 N ± 2N.
For those designing equipment for use in remote or rugged military or outdoor environments or where switch replacement is difficult, APEM’s new line of switches offers an excellent option.