Safe-Operation Savvy

Operators and users expect designs to be safe, and have increasing expectations for safety. For system engineers to provide this safety, they need switches that either the user contacts or ones that activate based on another action such as opening a door. For high-temperature applications, safety means the ability to withstand the high temperature, still operate properly, and not expose the user to an unsafe situation. Two safety switches and a high-temperature switch demonstrate products that make the world a slightly safer place.

EMERGENCY STOP SWITCHES

IDEC designed its XA and XW switches for improved emergency stop applications in factories. Available in 29 and 40 mm, the switches have the option of replaceable ac/dc LEDs offering increased safety. New “safe break action” technology helps prevent personal injury and major emergency events. In the heat of an emergency, a stop switch may be hit with excessive force to halt machinery. This force may dislodge a critical part causing a normal spring loaded switch contact to stay closed thus not stopping the machine. In contrast, the XA and XW series reverses the energy direction and uses the spring-pressure to assure that the NC contacts will open and stop the machine. If the emergency switch is damaged, the contact blocks separate due to excessive force or even if they are welded. The LED illuminated E-Stop switches allow workers the ability to quickly see the switch and apply normal pressure to stop the process. Get more information on IDEC’s XA and XW series of emergency stop switches.

ROCKER SWITCH

Tyco Electronics “tamper switch” deactivates machinery when access panel covers are removed for maintenance or repair. Rated up to 21A at 125 to 250V ac or 3/4 hp and operation up to 6,000 cycles, the safety switch uses silver-tin oxide contacts. With an actuation force at 425g, the switch’s actuator travel range is 0.345-inch. The switch’s nylon 6/6 UL 94V-2 housing uses 0.250-inch quick-connect tabs for wire connections. Targeting applications in air conditioners, furnaces, air cleaners and power control panels, the rocker switch is RoHS-compliant and UL approved. Get more information on Tyco Electronics’ tamper switch.

HIGH TEMPERATURE SWITCH

Designed to withstand up to 200C operation, Omron’s new high-temperature unsealed switch targets safe use in cooking applications such as ovens, rotisserie cookers and timers, and more. For high-temperature performance, inherent flame retardance and chemical resistance, the D3V miniature N Switch, rated at 11, 6 and 0.1A, uses Polyphenylene Sulfide (PPS) plastic molding compound. Operating up to 200C, the 6A and 0.1A switches are VDE and UL approved and the 11A operates up to 155C with approval pending. With either internal or external fitted levers and two fixing positions for external levers, the switches have a choice of terminal options. The switches are offered in SPDT, SPST-NC and SPST-NO configurations and have the same contact layouts and actuators ranges as standard high-temperature switches. The RoHS-compliant units conform to EN 61058-1, UL 1054, CSA C22.2 and UL 858 requirements. Get more information on Omron’s UL Class N Switches.