26 March 2014
Jane Alexander, Deputy Editor
An upgraded design for plugs and receptacles reduces shock potential in wet environments.
Opening a successful craft brewery was the dream of a lifetime for Mike Stevens and Dave Engbers, who started Founders Brewing Co. in Grand Rapids, MI, in 1997.
After some initial challenges, the partners succeeded at brewing a flavorful brand of complex ales with broad market and critical acceptance. Founders’ products are now available in 25 states.
To accommodate growth, the brewery recently needed to expand operations and increase the size of its production staff. Part of that effort involved enhancing worker safety. Despite the company’s excellent safety record, a brewery’s normally wet environment poses an ongoing safety issue with regard to electrical shock, particularly when workers connect and disconnect mobile pump carts. To address this issue, the company contacted local distributor J.P.Motors & Drives, Inc., who recommended Meltric Decontactor Series switch-ratedsafety plugs as a convenient and cost-effective means for improving brewery safety.
Alec Mull says Meltric’s technology (inset) makes the brewery’s pursuit of safety and productivity easier.
While pumps, motors and conveyors are among the primary sources of accidents at breweries and other manufacturing operations, the danger level at breweries can be high due to a concentration of factors such as hot liquids, pressurized systems, confined spaces, caustic chemicals and electrical shock. According to OSHA, electrical-shock accidents at breweries have occurred while technicians work on energized equipment like power panels and motor controls. To combat this risk, Founders installed Meltric’s plugs and receptacles on mobile pump carts, keg washers, motors and other portable equipment. According to Director of Brewery Operations Alec Mull, the plugs “help prevent electrical safety accidents before they happen.”
Because making and breaking connections with Decontactor plugs is a Risk Category “0” operation, PPE is not needed.
Many breweries use pin-and-sleeve, twist-lock or bladed-style electrical plugs to connect equipment to electrical power—all of which can be dangerous for personnel working in a wet environment. That’s not the case with Meltric’s connector technology. “We sell Meltric products to businesses that use portable equipment,” says David Patchak, a representative at J.P. Motors & Drives, Inc. “And we tell them that if an outside contractor on their site attempted to disconnect an energized pin and sleeve plug, it would be an OSHA violation that the site, not the contractor, would be liable for should an accident occur.” Patchak believes Meltric eliminates this problem with the safety features it incorporates into its products (see Sidebar below).
Their modular design and flexible mounting accessories allow Decontactors to be used in a variety of configurations, including, in-line, cord-drop or wall-mounted.
“Safety is a keyword at Founders,” says Mull. “We’re in a wet environment all day, and we don’t want to put our staff at risk. Meltric’s plugs were the most cost-effective and the safest product we could secure.” He adds that because the brewery does not always have an electrician on site, the plugs are convenient. Making and breaking connections with the Meltric plugs, for example, is easy. The work is done by an integral spring-loaded mechanism instead of the user’s physical motion (which is what typical pin-and sleeve or twist-type plugs require). In the Meltric product, the circuit is opened by depressing the pawl, which releases the energy in the spring-loaded operating mechanism, instantaneously breaking the circuit and ejecting the plug to the OFF position. The time needed to break contact is about 15 milliseconds, and the quick-break mechanism is automatically reloaded when the plug is re-inserted.
“Meltric connectors make the pursuit of both safety and efficiency much easier,” says Mull. “These are simple and safe devices.” MT&AP
Worker Safety & Switch-Rated Functionality
Meltric’s Decontactor switch-rated technology combines the safety and functionality of a disconnect switch with the convenience of a plug and receptacle. These features make Meltric plugs well suited for breaking electrical connections on the portable equipment that’s typically found in breweries. Safety is increased due to a design that causes load making and breaking to occur in an enclosed arc chamber shrouded by a safety shutter so users are isolated from live parts. The plug cannot be physically removed from its receptacle until the load is safely disconnected.
Meltric Decontactor plugs and receptacles are Type 4X, providing watertight connections for washing down production equipment.
To obtain the functionality of a disconnect switch within a plug, Decontactors are built with spring-loaded, butt-style contacts similar to those used on contactors and switchgear. Using end-to-end contact mating instead of sliding contacts provides a solid connection, and the spring loading produces optimal contact pressure, which ensures that the integrity of the electrical connection is consistently maintained over thousands of operations.
Decontactor plugs are fitted with silver-nickel contacts instead of softer brass contacts. A brass contact generally has poor contact resistance, resulting in a tendency to arc, which causes pitting, oxidization and shorter life. Silver-nickel contacts offer increased resistance to contact pitting, inhibit the destructive effects of corrosion and typically have a long life span of reliable use.
Decontactors feature spring-loaded, butt-style contacts similar to those used in contactors and switchgear.
Meltric Decontactors are UL/CSA rated for “motor circuit” and “branch” circuit-disconnect switching. They are an approved NEC/CSA “line of sight” disconnect switch.