• What metal tags would you recommend?
There are many different considerations for choosing the appropriate tag for an application. Sometimes it comes down to the best price or the physical size and the form factor of the tag; but often it is the read range or the tag material, mounting material, attachment method and surrounding atmosphere (including the presence of metal, humidity, current, etc.) that affects the durability and the performance.
• Why is the read range of the tag different from lab tests?
Sometimes RFID tags are modified for use in the rugged environment, by adding a protective coating or using spacers so the tag isn’t mounted directly on metal. These measures can significantly reduce performance for tags that were not designed to be attached this way.
Very often, the read range of the RFID tag is reduced due to frequency detuning, especially when the tag is embedded or used in a metal rich environment. Non-optimized tags may work sometimes, but consistent performance requires an optimized product.
• How can the item be tagged?
Sometimes the RFID tag itself can perform fine in harsh environment, but the biggest challenge is keeping it attached to the item. A metal tag may withstand high temperatures or immersion in liquid, but its adhesive may not. Ideally, an RFID tag will be embedded within the item it is identifying, which provides maximum protection against impact and exposure. Embedding isn’t always practical.
Adhesive is one of the more common ways to attach a tag to an item. Choosing the right adhesive requires an understanding of the complete environment, not just the working conditions. Extreme cold can also affect adhesives and can make tags brittle, so consider storage and processing temperatures when specifying tags. Adhesives however won’t work for all environments and materials, so tags may need other attachment options such as screws or rivets, string ties or epoxy.
• What potential sources of interference are in the environment?
Just because a tag is not applied to a metal object doesn’t mean it does not need to resist interference from metal. Tagged objects may be placed in metal carts or racks, or moved to areas where there is a lot of metal. Carefully consider all the areas where a tagged object will be used or may need to be read so you can select a model that will provide reliable performance.
• Can a high temperature RFID tag meet different high temperature applications?
In general, no. High temperature RFID tags are subject to different use applications. For example, a tag designed to work well in dry heat may not work well in an autoclave application that sterilizes with steam under pressure, nor does it necessarily meet all the other conditions of the high temperature application.