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  - Sept, 30, 2010 -  

RFID News: GS1 Issues New Guidelines for Pallet Tagging

  
 

Many Points of View on Tag Placement and Data Structure; Need to Address both the Asset and the Load

  
 

 

SCDigest Editorial Staff

SCDigest Says:
Recent research from the Technical University Munich found that different RFID reading equipment (gate, truck-mount, forklift antenna) used has a major influence on the optimal tagging location.

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GSI EPCGlobal earlier this month released new guidelines for tagging pallets with ECP-based RFID tags.

The issue is an interesting one, because there are two primary purposes for pallet tagging. The first, primarily for re-usable pallets, is to track and manage the logistics asset itself. The second it to track the goods on the pallet.

This means that potentially two identifiers are needed: one for the asset, one for the load at a given point in time. At other times, re-usable pallet companies may care only about the former, while shippers may care primarily about the latter. However, in many cases both sets of data will be useful.

The identifier for the asset itself is call the GRAI, which is the GS1 Identification Key used to identify Returnable Assets. The key comprises a GS1 Company Prefix, Asset Type, Check Digit, and optional serial number.

The identifier for the load itself is call the SSCC, which is the GS1 Identification Key used to identify logistics units. The key is comprised of an Extension digit, GS1 Company Prefix, Serial Reference, and Check Digit.

It will vary for each company, but a graphic below in the new guideline gives one view of where these IDs might be relevant for supply chain/logistics processes (a) or asset management needs (b) across distribution activities.

The guideline then breaks this down with similar categorization by specific processes (order picking, inventory control, etc.).

 

 

 

Source: GS1 EPCGlobal

Tagging Practices are Varied

One of the interesting points in the document is that there have been many views on the proper ways to tag pallets by pallet providers. For example,

 

A North American pallet company optimizes RFID tagging solutions subject to pallet type (material/dimension) and use case. On its most common wood pallets the company today recommends using 2 GRAI encoded EPC tags positioned at each diagonal corner of the pallet. The company further recommends the association (if desired) of the GRAI to other GS1 keys, e.g. SSCC, be made as a virtual association in the supporting information systems. As technology evolves the company will continue to optimize solutions based on read performance, cost and durability.

 

 A European pallet company is using 2 tags in the corner opposite to each other. The tag contains three sections. One with the GRAI, the second stores a password and the third is available for SSCC or any other information.

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A Korean pallet company uses one tag in the middle of the pallet with the GRAI stored. Over 30k pallets are already in circulation.

 

A European pallet association has tested and approved that one tag on the side gives the best results considering the different products loaded and the manufacturing process of the pallet. The tag contains today only the GRAI. An additional usage of the memory for the SSCC could be supported.

 

 An European pallet company is using 2 tags in the corner opposite to each other. The tag is currently a Dogbone Rafsec with NXP tag 512bits. They are looking for additional sensitivity of couple (tag,reader) in order to increase interest from retailers and industrialists.

 

The document cites recent research the Technical University Munich that found that different RFID reading equipment (gate, truck-mount, forklift antenna) used has a major influence on the optimal tagging location. The test results show that the solution that works in most settings is to place two tags into opposite corners of a pallet.

That research also found that a very important influence factor is the tag orientation, as not all systems operate with a linear polarization /uniform orientation. The recommendation is to place the transponder in an angle to allow all systems to work. A horizontal or vertical placement only should be avoided.

 

 

Source: GS1 EPCGlobal

Given that diversity of opinion, GS1 undertook research in terms of a variety of discussions with those involved with pallet tagging. That led to the following minimum tagging requirements in the guideline, described below and illustrated in the accompanying graphic.

  • A minimum of two RFID tags should be placed on a pallet in order to assure a minimum process security
  • Wooden pallets should have one RFID tag on the longer side and one tag on the shorter side of the pallet
  • Plastic pallets should have one RFID tag in the corner and another RFID tag in the opposite corner of the pallet

 The document notes there were also big debates of what the data structure options for the tags should be, with a wide number of scenarios promoted by different companies.

 

In the end, the recommendation was to consider one of three options:

 

  • Use a GRAI tag only: Main disadvantage is that the load ID (SSCC) can only be linked by the software, with no ID on a pallet tag.
  • Have separate GRAI and SSCC tags on the pallet: Some reduction in read/write speeds, and may requires robust processes to update the tags consistently. There is a risk of having the wrong (an old) SSCC in the tag as the pallet moves.
  • Use a GRAI tag and put the SSCC number in the tag's "user memory": Slowest read-write tags, and again some risk of failure to update the SSCC number.

 

The full guideline is available for free download at the GSI EPCGlobal web site: RFID Pallet Tagging Guideline

 

 

What's you reaction to this new guideline for pallet tagging? Useful or not? What has been your experience about what works well? Let us know your thoughts at the Feedback button below.

  
     
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