Automation 101

Power-supply manufacturer Carlo Gavazzi recently released a series of switching devices the company deems "economically friendly," the RMD Hybrid Relays. The product provides mercury-free switching, designed for controlling heating elements inside of food ovens, warmers, fryers, rotisseries and other food equipment. It's capable of switching up to 20 cycles per minute, with a 4 million electrical cycle life expectancy.

The RMD Series combines solid-state technology and electromechanical relays to provide a hybrid relay. This means that there is virtually no contact arcing, which  results in prolonged relay life and much less emission inside of the panel. Another benefit of hybrid technology is a full amperage rating at elevated operational temperatures. While most conventional switching devices are rated at 25-40 degrees Celsius, the RMD Hybrid Relays are fully rated up to 60 degrees Celsius. The RMD3H switches heaters on three legs while the RMD2H is a lower-cost alternative, as it switches two poles and the third pole is directly connected between L2 and T2. Additional technical features include:

• Two- (for single and three phase circuits) and three-pole arrangements
• Rated for 4 million electrical cycles
• Rated for up to 20 cycles per minute
• Two output voltage ratings: 240VAC (VL-L) and 277VAC (VL-N – 480VAC with Neutral)
• Three common control voltages: 24VAC, 120VAC, 240VAC
• Two amperage ratings: 30A up to 70 degrees Celsius, 40A up to 60 degrees Celsius
• Similar mounting to Mercury Displacement Contactors
• Mercury-free, RoHS compliant, cRUus recognized