
Safety Push Buttons

Pilot devices provide control and condition monitoring of different types of processes, equipment and machinery in industrial and commercial applications. They are used for communication from a machine to an operator or from an operator to a machine. Pilot devices can be an audio or visual indicator, or an actuator that is used to control the flow of energy to a process. Visual indicators are: pilot lights, signal towers, strobes and beacons. Audio indictors are: buzzers and sounder horns. Actuators are: push buttons, selector switches, toggle switches and potentiometers.
Push button are most commonly used for switching devices on or off. There are different types of push buttons switches that function in specific ways. Momentary push button switches require continuous compression to keep contact within the circuit and keep the device “on.” Most are used for intermittent user input such as reset or keypad buttons. Latching or maintained push button switches do not require continuous compression and require the user to just press the switch once to turn the device on or off until it is pressed again.
It is important to follow the proper safety standards when selecting the color of push buttons for industrial applications in order to prevent confusion. Start/On function: Green, white, black or grey. No red. Emergency stop function: Only red. Stop/Off function: Black, grey or white. No green. Red is permitted if it is not near any emergency stop buttons.
Push buttons designed for industrial environments should have proper sealant methods to prevent water, oil and other pollutants from interfering or contaminating the mechanism. They should be built to withstand higher voltages and the switches should allow for greater electrical conductivity. They generally come in 16, 22 and 30 mm sizes, can be illuminated, and are available in metal and plastic versions.
Products
E-Stop Categories
E-Stop buttons provide the ability to cut power to potentially dangerous hardware in case of an emergency. This stop function should occur without causing any additional unsafe conditions. E-Stop circuits are typically used with safety-rated hardware, such as safety relays.
There are different E-Stop categories that determine how machinery will behave once the stop is actuated
Stop category 0 function
Stop category 0 function works by immediately killing power to the hardware connected to it. This is the fastest and safest way to provide a stop function for an E-Stop safety circuit. It should be noted that additional electrical or mechanical action may still occur to more quickly provide a safe environment, such as braking.
Stop category 1 function
Stop category 1 function does not immediately shutoff power, but provides a delay before mechanical disconnect. This function is common when it is necessary for a certain process to finish a movement or cycle, or to wind down before it is safe to shutoff power. This category is also used when cutting power immediately can create a dangerous environment for the operators in the area of the equipment. By allowing for a delay to occur, it provides time for machinery to safely shut down.