Powering production in food plants is not as simple as throwing a switch. Peak-time charges, outages, surges and other factors can complicate calculations of cost and reliability and require solutions that go beyond standardizing on premium motors.
The good news is that OEMs are delivering solutions on multiple fronts, from systems approaches to power delivery and servo options to sanitary design improvements and smart motors.
Maintenance is leaping from Internet of Things hype to shop-floor predictive maintenance with a condition monitoring device from ABB Inc. (www.abb.com). Called the Ability Smart Sensor, the device is priced in the low three figures and monitors vibration, current and temperature to assess bearing condition, operating temperature, air gap eccentricity and rotor winding health.
Initially, food maintenance technicians can check the health of motors through a smart phone app; in April users will be able to upload data to a cloud server for trending and other analytics, according to Kyle Davis, smart sensor technical support engineer in ABB’s Greenville, S.C. facility. “With the Internet of Things (IoT), new features like percent loading can be added with a firmware release.”
Slightly larger than a deck of cards, the sensor is attached to a motor’s fins with a two-part epoxy. The unit is motor agnostic, though it will be factory fitted to severe duty NEMA motors manufactured by ABB’s Baldor Reliant division when availability catches up with demand.
Compatible with motors up to a NEMA 449 frame, the diagnostic tool is specific to the motor it is attached to, Davis explains. End-users register the sensor’s serial number and the motor’s load bearing size, frequency and other specifications to generate diagnostics specific to it.
A traffic light display of green, yellow and red lights provides an at-a-glance assessment of the motors in a facility. A numeric score also is delivered. “Anything over six is an alert,” with service recommended at the next opportunity, he says. “Over 10 is critical.”
Thousands of the smart sensors already are deployed in Europe. U.S. installations were delayed until UL certification was secured. Based on early results, end-users are realizing a 70 percent reduction in downtime.
“It’s that extra tool in your bag and your first line of defense to assess condition and move you to predictive maintenance,” Davis concludes.
Energy consumption also is reduced, though given the power loss that occurs when rotating motion is converted by a gear or drive, a system’s approach is needed for optimal performance. SEW Eurodrive demonstrated that truth with Movigear, the mechatronic drive system that combines motor, drive and inverter.
The concept is coming to drum motors in the second quarter when Toronto-based Van der Graaf Inc. (www.vandergraaf.com) commences production of its integrated DFI frequency inverter within a drum that includes the motor and drive. Owner Alex Kanaris calculates the energy savings at 70 percent.
Drum motors have a 30-year track record of powering conveyor belts, though reliability issues and food-waste accumulation kept them out of many food-production environments, particularly meat and poultry. Kanaris credits his firm’s work in the mining industry with helping it resolve the reliability issue. Sanitary design led to improvements like a 316 stainless steel drum with motor, gear drive and all moving components enclosed. Compared to a conventional drum with an external drive and no permanent magnet, the system produces about a 25 percent energy savings.
“It’s a three-phase motor with an electromagnetic field in the rotor that boosts the stator,” he says of the assembly. The addition of a digital frequency inverter enables speed control with an IoT connection. The drum assembly comes with its own IP address, though it also can be controlled through a local network.
Incorporating the frequency inverter into the assembly increases the importance of the motor encapsulation process that Van der Graaf calls vacuum pressure impregnation. Epoxy typically is added to the motor cavity to encapsulate wiring and harden the windings to prevent premature failure. Any air pockets in the epoxy can pick up a charge from static electricity and destroy the motor when it discharges.