Best practices for RFID tag installation

While not recommended, you can recess a standard RFID tag into metal by following all three guidelines below. Be sure to test this installation thoroughly.

1. Provide a plastic or epoxy spacer between the tag and the surface. For best results, the spacer should be a minimum of 10 mm or ½ of the tag diameter, whichever is larger.
2. Size the recessed area at a minimum of 2 times the tag diameter.

As shown in the image:

1. Standard RFID tag with diameter D
2. Plastic or epoxy spacer
3. Metal

Tip:  A smaller recess may be possible, but this may create an inductive current that will affect the reliability of the installation. In some cases, a radial cut in the metal surface may be enough to interrupt the induction current.

3. When selecting an antenna for this installation, consider the size of the inductive field. A flush mount antenna has a more confined field than a non-flush mount antenna. Similarly, a smaller diameter antenna has a smaller field.

Mounting pre-tuned RFID tags

ifm offers tags that are pre-tuned to provide maximum reading distance when mounting directly on metal. These specialized tags can also be applied to non-metal materials.

Allow a metal- / moisture-free zone of 2 times the tag diameter adjacent to the tag as shown in the image.

1. Pre-tuned RFID tag with diameter D
2. Non-metallic material
3. Metal

Allow a metal- / moisture-free zone of 2 times the tag diameter in front of the tag as shown in the image.

1. Pre-tuned RFID tag with diameter D
2. Metal

When recessing a specialized RFID tag into metal, follow both guidelines below.

1.  Size the recessed area at a minimum of 2 times the tag diameter as shown in the image.

1. Pre-tuned RFID tag with diameter D
2. Metal

Tip:  A smaller recess may be possible, but this may create an inductive current that will affect the reliability of the installation. In some cases, a radial cut in the metal surface may be enough to interrupt the induction current.

2.  When selecting an antenna for this installation, consider the size of the inductive field. A flush mount antenna has a more confined field than a non-flush mount antenna. Similarly, a smaller diameter antenna has a smaller field.

Fully embedded tags

Some applications require a fully embedded tag, for example in a metal tool. ifm offers one tag, E80381, which is tuned especially for this type of application. Note the reduced read distance in the table below.

Mounting high temperature RFID tags

ifm offers specialized tags to withstand exposure to very high ambient temperature while retaining their stored information. Note that the tag and ambient temperature must be within the operating range, post high temperature process, for accessing the data.