Passive RFID measures and reports resistance – delivers sensor read-out function

June 13, 2014 // By Graham Prophet
Farsens’ RMETER is a battery-free RFID resistance meter tag: it is a full passive RFID tag that measures the resistance value of the device connected to it with a 10Ω to 10 MΩ range.

The RMETER RFID sensor tag transmits a unique identifier and the associated resistance measurement data to a commercial EPC C1G2 reader without the need of a battery on the sensor tag. This device can measure resistances in a range from 100 Ω to 500 kΩ with an accuracy of ±3%. It also offers an extended operation range from 10 Ω to 10 MΩ with an accuracy of ±7%.

The RMETER has a 96 bits EPC number, a 32 bit TID and a password-protected Kill command. The tag comes in a variety of antenna designs and sizes to adapt the performance to the required application in the 860-960 MHz band. The reading distance for the battery-free thermistor tag is around 1.5m and it can be embedded in a wide variety of materials such as plastics or concrete. It can also be encapsulated in an IP67 or IP68 casing for usage in harsh environments. Evaluation kits are available.

The RMETER can be used without batteries, allowing for a wide range of opportunities monitoring resistance in applications where the accessibility is restricted, or where the use of batteries is not recommended.

RMETER tags offer R&D teams the opportunity of using proprietary resistance based sensors in battery-free mode. Typical resistance based sensors include thermistors, light dependent resistors (LDRs), soil moisture sensors or strain gauges amongst others.

Farsens (Spain); www.farsens.com