Sensitech’s RFID Cold Chain Solution

By Mary Catherine O'Connor

The cold chain technology company has RFID-enabled its TempTale sensors and developed a platform for end-to-end temperature-tracking of perishable foods.

Sensitech, a company that manufactures temperature-tracking products and provides integration and data analysis for the food service and pharmaceutical industries, has released an RFID-enabled temperature-tracking product. This system is designed to give companies end-to-end visibility into their cold chains and alert cold chain partners when their product is in danger of falling outside the acceptable temperature range. Trials of the system showed that companies could use the Sensitech platform to reduce inventory shrink due to spoilage by as much as 15 percent, the company reports.

More than 3,000 produce growers and shippers, and 20 grocery chains, currently use Sensitech's non-RFID TempTale temperature monitors. However, because the devices must be physically removed from the flats or pallets of perishable products to download the temperature history, they are used to provide a history of only one leg of the food's journey at a time. This temperature data can then be utilized for conflict resolution between supply chain partners—for example, a retailer might use TempTale data to make a claim with a grower or shipper if goods received were spoiled.


Sensitech's TempTale tags are built into active RFID transponders.

With this RFID-enabled application, called ColdStream Plant to Shelf (PTS), the TempTale devices are built into active RFID transponders. These are placed inside pallets or cases of perishable product before being put into transit. The sensors periodically record and store temperatures, and the 915 MHz active tags transmit temperature data to interrogators (readers) installed in warehouses, distribution centers and retail locations. This data is then collected centrally, and the PTS system sends alerts to supply chain partners when there is a danger of perishables becoming too warm or too cold.

"We believe this product offers end users an ROI in two main areas," says Rupert Schmidtberg, Sensitech vice president and chief technology officer. "First, it can reduce inventory shrink, which leads to improved operational efficiencies. Second, by improving temperature controls, users will improve the quality of the food they sell, which will retain existing customers and attract new ones. And in a world where Wal-Mart is taking other retailers' business on a price-competition basis, you'll find that more and more, retailers are turning to perishable goods to attract and retain customers. So if the quality of your perishables is important to you, how are you measuring it? If you don't measure it, it's hard to manage it."

A Sensitech retail client that participated in an early test of the PTS application tracked perishables from its DC to a retail location. Previously, it had not tracked this leg of the cold chain because the TempTale devices were removed at the DC. The client found that three commodities (chicken, berries and bagged salad) arrived at its store an average of 5 to 7 degrees Fahrenheit warmer than specified. Equipped with this data, it could change its in-transit operating procedures for the DC-to-store trip so that the three commodities would be kept at an optimal temperature.

Sensitech manufactures the hardware used in the PTS system. This includes TempTale tags, gateways (interrogators that connect to a PC through an Ethernet link) and repeaters, which are also interrogators but do not connect directly to a PC. Each facility where produce is tracked needs one gateway within read range (300 feet) of at least one repeater.

Repeaters are placed at the dock doors and throughout each facility. Each repeater has a 300-foot range, both for reading TempTale tags and relaying this information to other repeaters. Each repeater reads any TempTale tags within its range. It then sends this RFID data, along with a unique ID referencing its location, to the gateway, via a mesh network of other repeaters. The gateways can also read TempTale tags within a range of 300 feet.


Repeaters are placed at the dock doors and throughout each facility.

The gateway is linked, via a PC, to a Windows-based remote-site server (RSS) at each facility. RSS is a software agent that downloads and forwards the data to a central repository, via a secure network connection. Users install the system wherever in the cold chain they want to gather temperature data. The system could be used for tracking one segment of a perishable goods' journey, such as from a processing plant or farm to a distribution center, or between a retail distribution center and retail locations. Or it could track every leg, enabling a complete history and the most visibility into the product quality. The RSS also monitors the health and readiness of the repeaters and gateway.

The central repository that collects the data from all of the RSSs is Sensitech's ColdChain Visibility Server, a Web-based hosted database application written on Microsoft's .NET platform. The application can be used by all participating cold chain partners. Access to the application and its data is established through passwords. Temperature-related alerts can be dispatched to cold chain partners via e-mail, or partners can query the data on an ad hoc basis.

The ColdChain Visibility Server is used to generate reports detailing the temperature histories. Sensitech also offers professional services to help partners analyze their data and draw conclusions about the efficiencies of their cold chain management processes.

Retailers are the most likely cold chain companies to purchase the PTS system. They could pick up the entire cost or negotiate with their cold chain partners to share the expense. Sensitech customers could even charge their supply partners for access to their shipment data. Sensitech claims that it would cost a retailer approximately $600,000 to deploy the PTS system across 500 stores and three DCs that handle 10,000 shipments per year. Based on projections, they would save $250,000 per store annually, through reduced shrink.