Industrial remote controls are wireless input devices that are used to control machines and equipment to which they are not directly linked. They use radio frequency (RF) signals, digital pulses, or infrared light to send signals from transmitters to receivers. With RF devices, an antenna is attached to the receiver or installed separately to improve reception. Rugged housing or standard enclosures are used to protect sensitive components and are suitable for indoor or outdoor use. Some industrial remote controls include only a transmitter such as a keypad, paddle, pushbutton, or toggle switch. Others include only a receiver. Complete systems include a matched transmitter-receiver set called a transceiver.
Industrial remote controls vary in terms of performance specifications, configurations, transmitter displays, and receiver displays. Performance specifications include number of inputs, outputs, and channels; operating frequency range; and operating distance. Measured in feet (ft), operating distance is the maximum distance at which working transmitters and receivers can be placed apart. In terms of device configurations, some industrial remote controls are handheld or portable. Others mount on a console or sit atop a desk or workbench. Transmitter displays typically include analog indicators, light emitting diodes (LEDs), or digital readouts. Receiver displays usually consist of analog meters, digital readouts, or video displays that use either cathode ray tubes (CRTs) or liquid crystal displays (LCDs). Multi-line forms are also available.
There are a variety of features for industrial remote controls. Some devices are computer programmable, battery powered, or electrically shielded. Others have a weatherproof housing or are designed to operate in extreme environments with high levels of temperature, humidity, and dust. Intrinsically safe devices will not create a spark and are designed for use in areas with a potentially explosive atmosphere. Other safety features include emergency stop switches and overrides. Organizations such as Underwriters Laboratories (UL) approve or certify industrial remote controls according to standards for safety.
Industrial remote controls are used in many applications and industries. Examples include aerospace, agriculture, automation, construction, data acquisition, and forestry. Industrial remote controls are also used to control material handling equipment such as hoists, cranes, lifts, and winches. Basic devices are used to control pumps and machinery. Specialized products are used in shipyards and by the military.