Sensors are making their way deeper into process manufacturing where they monitor PH levels in vinegar, ensure towering bins of sugar aren’t overfilled and measure humidity in bakeries. Sensors are even helping power better mousetraps.
But some plant managers are skeptical about sensors because the sensors installed in the 1990s or early 2000s don’t have a good communication system, aren’t the right tool for the job or simply don’t work.
“Plant managers tell me, ‘We’ve had sensors on top of those silos for a long time and they really don’t work,” Mike Mossage of BinMaster said. “We often find in food and beverage that some manufacturers are relying on outdated sensors for inventory management or relying on sensors that are limited in terms of communication options. When some of the older ultrasonic and radar technologies hit the market in the 1990s, a lot of them were oversold regarding performance. Honestly, they were misapplied at the outset.”
“Manufacturers may not realize all the advances made in sensors since then,” he said. “Manufacturers need to make sure they choose the correct sensors at the outset of the project to make sure they’re going to be a good fit.”
Sensor technology is worth a second look. Better sensor performance, improved Bluetooth technology, longer battery life and dramatically lower sensor prices are helping to power this transformation. Those lower prices are bringing more sensors into process manufacturing in the food and beverage sector.
ROI can be as little as one week.
Like every other manufacturing sector, the food industry needs to monitor motors, pumps, fans and refrigeration, Martin Armson of Hansford Sensors said.
But in the past, the cost of sensors and associated technology couldn’t be justified.
“At one time, the food industry was not a market for us,” he said. “No one ever considered the machines were big enough, costly enough or that any processes were critical enough that they could afford to spend $1,000 per measurement point.”
Increasingly lower sensor prices—which open the door to monitor smaller, less powerful equipment—spurred Hansford Sensors to enter the food industry, Armson said.
“What’s really changing is the cost per measurement point. That’s the biggest trend in the market,” he said. “As a result, you can measure smaller and smaller machinery. Now that the cost is down to $200 per measurement point, many more machines are becoming prime assets.
“At one time, unless it was a 500-5,000 hp motor, you wouldn’t monitor it. Now you’re getting down to where it’s cost effective to monitor a 10 hp motor. Food has become a significant part of what we do.”
Fast ROI gets the attention of plant managers.
“One of our best use cases is one of the world’s largest dairy producers,” Jay Wright of Somax Sensors said, declining to name the company. Food and beverage companies comprise 70 percent of Somax’s clients.
“Within the first week, our sensors identified two issues and were able to save so much down time that it paid for a year of service,” he said.
In each case, the sensors detected an abnormal temperature. In the first case, a machine had not been properly lubricated for some time and the motor was overheating. In the other case, a machine had been set up improperly by production personnel.
In both cases, maintenance teams were able to correct the issues before they caused damage to the affected machines and took down the production line, Wright said.
At $35 an hour (including the cost of benefits), a technician inspecting a piece of equipment once a week in about half an hour costs you about $900 per year, he said. But a $100 sensor with $24 in annual monitoring costs can also get the job done.
In the past, even companies with computerized systems relied on paper, Wright said. “We had a computer system that generated paper work orders; we handed those work orders to a technician who filled them out and then someone else sat down at a computer and typed them in.”
Today, workers rely on tablets and smart phones, eliminating the paper trail and the need to retype information.
Often the first challenge is convincing operations mangers—many of whom have old, costly sensors that provide little or no value to their plants—that today’s sensors actually will make a difference.
But once the sensors are deployed, new use cases quickly come to mind.
Old sensors, inaccessible data
About three years ago, Swift Sensors CEO Sam Cece faced a team of operations managers at a Kraft Heinz plant in Illinois, where the company makes many of its signature products, including ranch dressing and macaroni and cheese.
Cece wanted to help the plant automate their manual process of checking temperatures of ingredients and finished products.
“They have to make sure their machines run 24 hours a day so they can get product out the door,” he said. “They have to check temperatures and document it for each one of 30-plus coolers. The secret sauce in a lot of these products is vinegar. If vinegar goes over a certain temperature, it increases the PH and it’s out of compliance.”
When Cece visited Kraft Heinz, he saw the company already had sensors but was not gaining benefits. Instead, the company relied on manpower.
The company’s procedure to monitor cooler temperatures involved one employee riding around the 40-acre plant in a club car, checking each cooler, writing the temperature down on a piece of paper and sticking that paper in a file folder. If any product or raw ingredient was out of spec, that product/ingredient had to be discarded.
“As I’m walking the plant taking my tour, there were a bunch of sensors all over the place,” he said. “I asked my contact: ‘You have a bunch of sensors, already. Why are you talking to us?’ He told me, ‘These sensors are about $5,000 each. They’ve been here about 15 years and we’ve never once used them. We have no idea how to access the data or what to do with it.’ That’s why they called us.”
Since Kraft Heinz wasn’t using its current sensor system, plant operators were understandably suspicious of throwing more money at sensors and automation.
“I had nine guys in hard hats with their arms crossed, very skeptical about what I was selling,” Cece said. “These guys are very concerned about messing anything up.”
The plant manager, however, knew he had a need for faster data.
“He pounded his fist on the table and said, ‘I can’t get information fast enough to make a decision,’” Cece said. “‘That’s why I want this technology’.”
Swift put new sensors on one cooler. Within a couple of days, a plant manager called Cece—on a weekend—to discuss more potential use cases.
Within a week, the company won approval to deploy them throughout the plant.
Another example of earlier misapplication of sensor technology has occurred in plants with dusty environments, Mossage said.
For example, since ultrasonic sensors rely on high-frequency, sound-based technology, the signal has trouble pushing a signal through dust in the air and getting an echo back from surfaces, he said.
Similarly, the 26 GHz radar sensors require a horn on one end to focus the beam and that horn becomes covered in dust, leading to instability, Mossage said.
BinMaster offers three options tailored to food-production environments that are dusty.
The first is a yoyo-type sensor; BinMaster’s version is called SmartBob. A sensor probe is attached to a cable that descends to make contact with the material. The cable drops down, retracts and provides a level measurement of material in a bin.
BinMaster is seeing a move away from devices such as SmartBob that make direct contact with material. Instead, manufactures are opting for non-contact systems that require less maintenance.
BinMaster offers two non-contact options. A 79 GHz electromagnetic radar signal sensor measures time of flight as the signal echoes off the material surface and does not require a horn. A sound-based, low frequency 3D level scanner provides better accuracy for measuring volume because it measures peaks and valleys in the material surface. This sensor works reliably in dust because it operates in the same audible frequency as the human voice and the vibration that generates the acoustics keeps the transducer free of buildup, Mossage said.
Hansford Sensors focuses solely on monitoring vibrations, which can easily broadcast the health of a piece of equipment.
“If you have new pumps, anything brand new, your vibrations are smooth running,” Armson said. “That vibration is in proportion to the health of the machine. As the motor or pump deteriorates in condition or health, the vibration increases. As time progresses, the vibration gets progressively worse at an ever-increasing rate and eventually you get catastrophic failure unless you do something about it.”
Manufactures monitor vibration two different ways, he said: permanent machine monitoring and condition monitoring.
With permanent machine monitoring, sensors track vibration continuously, send the data to a PLC and look for a trend as the vibration increases, he said. When the vibration reaches a certain point, the system raises an alert.
“The system says, ‘I don’t necessarily know what’s wrong. But there’s a problem here. Come have a look at me’,” Armson said.
With condition monitoring, a vibration analyst periodically comes by with a cable and a sensor on a magnet and checks the equipment. The analyst, by looking at the data, can determine exactly what is wrong, for example if bearings or the gearbox are starting to show wear, he said.
Improved analytics help
At Kraft Heinz, Swift Sensors installed its sensors, each of which cost about $100, on top of the plant’s existing sensors, and then added a crucial component lacking before: an easy-to-use analytics package.
“The beauty of our system is you, as the user, can set it up any way you like,” Cece said.
If, for example, the material monitored is normally at 38 degrees F and must be discarded upon reaching 45 degrees, the plant manager can se a threshold so that at 40 degrees, you send “Johnny” to see what’s going on, he said. If the material remains at 40 degrees for longer than five minutes, you escalate it to “Bill,” a manager.
You can set multiple types of alerts. If the cooler typically goes into defrost mode and stays at 42 degrees for 20 minutes every 24 hours, you can set it so it doesn’t alert unless it stays at 42 degrees for longer than 20 minutes.
Other sensors offer similar options.
In a bakery, for example, dough won’t rise if the humidity is too high. Somax sensors and software not only alert technicians to issues and potential issues but also outlines what the technician needs to do to fix the problem, Wright said.
Somax sensors cost $50-$100 each and monitor temperature, humidity, vibration and fill levels.
“We can also look for trends,” he said. “For example, if the temperature increases more than one degree in one hour, that tells plant managers ‘we need to get someone out there’.”
Alerts can be set so that any problems don’t have to be addressed immediately.
“You can make an informed decision,” Wright said. “You can look at the production schedule and say, ‘We have a downtime window here to go in and change that motor’ instead of waiting for a failure.”
As in other industries, sensors help identify underperforming machines, compared with original specs, with the same machine on other shifts and with the same model machine in other plants.
“If one machine is producing 200 units per hour and the other is producing 160, we automatically know we have a problem,” he said.
OEMs also can use sensor data to monitor how their equipment is performing at client sites, suggest maintenance and replacement parts before problems develop, Wright said.
Eventually, once trust has been established, automated smart contracts will establish procedures where parts show up before a manufacturer needs them, he said.
“They’re giving performance guarantees on their equipment so they want to see the data—see that the machines are being properly maintained—and let the plant know what’s going on,” Wright said. “Somax wants to be the central platform to do that.”
Many decisions to make
Manufacturers have varied options for analytics and communications.
Customers can opt for a land-based server-client software system on a secure network available on a PC to anyone in the plant, Mossage said.
Or, they can use BinMaster’s BinView, which offers a cloud-based system that allows its customers to view the data anywhere they have internet access.
BinView is especially valuable for manufacturers without a shared network and/or facilities in remote locations without much infrastructure, he said.
“We’re definitely seeing more and more of the BinView,” Mossage said. “Anyone who has the log-in credentials can view the inventory information on a smart phone or tablet.”
For tracking inventory, some BinMaster customers set up their systems to receive an email or text alert when inventory drops below certain levels, he said, noting that some of his customers essentially don’t order raw materials. “Instead, they set their supplier up on a BinView program and when the supplier receives the alert, they send more raw materials.”
“Our biggest obstacle is the IT department,” Wright said. “They want control of everything. We have to go through all the testing.”
With that in mind, Somax has made an end run around IT.
“We’ve taken IT out of the equation,” he said. We have a web and cellular based solution. We’re not on their network. We’re not on their computers. We have a web and cellular based solution. We never have to involve IT. We put the sensors in, put a cellular gateway in and start pushing sensor data to the cloud. We put our mobile devices on the floor; they download our apps, and they’re ready to go.”
Another challenge for food and beverage is the method sensors are attached to machinery and the overall plant environment, Wright said. “You have to be careful how the sensors are attached. If there are gaps, bacteria or other contaminants can get in. Some sensors are used in wash-down environments where all the equipment is washed with high-pressure steam hoses multiple times a day. It’s important to have the right sensors in place that can stand up to the environment.”
An IoT mousetrap
Finally, sensors are even a valuable add-on to mousetraps.
Most food production facilities deploy mousetraps outside to prevent rodents from coming into the factory, Wright said.
“In the past, they had to be checked once a day or once a week to be cleaned out,” he said. “Now, we have IoT rodent traps with sensors, and when they engage, someone gets an immediate notification: ‘This trap in this location needs to be cleaned out’.”