RFID chips – function and differences between collar tags and implanted microchips explained

In addition to the control via motion detector, via remote control or app, the RFID control is just one of four options to open the petWALK door.


RFID technology has been used for a very long time (since about 1970), which is why the system is a little outdated and has its pitfalls. At the moment, however, there is no technically better solution that we could easily use in our products to substitute RFID technology.


The petWALK door has an RFID antenna built in, which theoretically can read both the RFID collar tags available in the shop as well as already implanted microchips of your pets. The antenna is located exactly in the middle of the door leaf (the moving part of the door). Please pay attention to the following information on the use of RFID tags and implanted chips with the petWALK pet door.



There are two kinds of RFID chips:

petWALK RFID collar tag


RFID collar tags

We offer RFID collar tags in two sizes. Each order includes an RFID collar tag; a medium sized chip for medium doors and a large sized chip for large doors.

In case you do not use the collar tag, e.g. if the door shall be operated with motion detection only, please keep the tag anyways. You might want to change the settings to RFID control at a later point in time or we might need to test the RFID functionality with you.

petWALK collar tags are shockproof and waterproof. If your dog loves to chew on things, you might want to order an extra tag just in case.

The large collar tag can reflect signals to the door sufficiently at approx. 20 cm (8 in.) from the center of the door, the medium chip is recognized at approx. 15 cm (6 in.) . The ideal detection range can be seen in the illustration below. Ideal conditions are e.g. the correct installation height, the correct approaching angle of the pet as well as the positioning of the chip to the antenna.

RFID detection range


petWALK Funktion mit RFID Chip implantiert


implanted RFID microchips

In theory, the petWALK door is also able to detect and read implanted microchip transponders. These must be as large as possible - but at least 12 mm in size - and comply with ISO standard 11784/11785 FDX-B.

The function of implanted chips, however, can not be guaranteed due to a variety of factors affecting their function, e.g. implant depth, position, location, etc. of the chips. The main drawback of implanted chips is their small size. The smaller the chip, the fewer copper spirals fit into the capsule, and the worse the mini chips can reflect the signals emitted by the door.

As implanted microchips were not designed to open doors, but to be scanned at the shortest distance from a vet, the recognition range is consequently lower. Microchips which are not yet implanted in the pet work at approx. 10 cm (4 in.). Once the chip is implanted, the detection range is only 0 to 10 cm (0-4 in.).

In general, the detection of implanted chips after the acclimation phase is sufficient for cats; depending on their size rather insufficient for dogs. This is simply due to the size of dogs - the longer the snout, the bigger the distance between the location of the implant (usually the neck area) and the antenna.

If the recognition of implanted chips is your main purchase criteria, make use of your extended right of return within 30 days. You can test the petWALK door with your pets for the function of the chips when still uninstalled. The following hints & tricks will make training with your pets easy. We are happy to assist if you need further information on the petWALK door's functions or programming support.

An external RFID antenna which can be mounted almost anywhere will increase the chances of chip recognition (particularly implanted chips) in the near future. This additional module can be retrofitted for any petWALK door in use.



Helpful hints & tricks for the use of RFID chips with the petWALK pet door:


  • the first weeks: Allow your pets to get used to the petWALK pet door in the first few weeks after installation. You may just leave the door in motion detection mode for some time. Your pet will recognize the petWALK door as its entrance during this time and get used to its functionality.

  • reduce the reading distance step by step: Once the animal gets used to the door, the detection range of the motion sensor can be gradually reduced. We call this process the adjustment phase. Your pet will slowly learn that it must come closer and closer to the door to trigger the opening mechanism of the door. We recommend to reduce the sensitivity of the sensors in steps of 5 or 10. Find out how this is done in the current user manual on p. 29 "5.6 ADJUSTING THE SENSITIVITY OF THE MOTION SENSORS". If you feel that your pet is now close enough to the door to be detected by the RFID antenna, save the animal's chips, found on p. 30 in the manual "5.7.1 PROGRAMMING AN RFID CHIP" and activate the lock symbol on the display as described in the manual on p. 24 "4.7.3 OPERATING MODE'RFID ACCESS CONTROL'".

  • Separate RFID control inside/outside: If your pet is afraid of the petWALK door (which might occur when the door opens towards them), the door can also be set to open - triggered by different modes - on the inside and outside. Should this be the case, we recommend to set the door to motion detection for the pet's exit (this allows your pet to go outdoors at your preset conditions) and setting the door to RFID recognition for the pet's entry (this ensures that only animals with stored chips will be able to use the door). See p. 31 "5.7.2 SETTING UP RFID ACCESS CONTROL FROM INSIDE AND / OR OUTSIDE"

  • Using the door with large and small pets: Should you decide to purchase the large door and intend to have it used not only by large dogs but also by smaller animals such as cats or smaller dogs, the distance between the neck area of ​​the animals and the center of the door leaf might be too large, considering the size difference of the animals. In this case, or if the door has been installed higher than recommended due to difficult installation situations, you can help the animals to get into the detection area of ​​the antenna with a simple step or a small pedestal.

  • Using several chips per pet: Since the position of the RFID chips to the antenna plays an important role in the detection, the use of multiple chips per animal is possible in extreme cases. These may be sewn into the collar. The door will open as soon as the first chip is detected.

  • RFID antenna for flexible installation: The prototype of an external RFID antenna is currently being tested. This antenna can be installed at a different height or location. Although both the functionality and the reading range of the external antenna are the same as the antenna installed in the door leaf, this new development can offer considerable improvement for all customers with the challenges described in point 4. Once the internal testing phase is completed, some customers will be able to order a trial version of the new product at a discounted price. Do you wand to be part of the test? Let us know: info@petwalk.at.

Sources of error and frequently asked questions:


Metal doors, aluminum shutters and RFID

Metal objects and RFID are not quite compatible. Metal reflects the RFID signals which is why a metal object in front of the petWALK door could interfere with the function of RFID. On one hand the signals are shielded and thereby prevent the detection of the pets' chips, on the other hand the signals are reflected so strongly that the RFID system is disturbed and an error message is displayed. This occurs e.g. when an aluminum roller shutter is lowered directly in front of the petWALK pet door. If aluminum shutters are planned to be installed in all windows of the house, we recommend to find an alternative location location for the petWALK pet door e.g. a wall next to the window.


Also, installation in metal doors is not recommended. An installation in doors with a metal core (e.g. entrance doors with a high safety standard), however, is no problem.

Attention: Metal doors can also be fire doors. Please note that the installation of a petWALK door in a fire door will result in the loss of fire protection. Although the petWALK door would likely withstand a fire very well, there is no certification.


petWALK Tiertüre neben Alurollos




Frequently asked questiosn (FAQ's)

For detailled information on RFID, please read the following FAQ’s or contact us.


What is RFID?

  • The abbreviation RFID stays for radio-frequency identification, which means identification by electromagnetic waves".
  • RFID enables the automatic identification and localization of objects and living beings.
  • An RFID system consists of a transponder, the microchip which is located on or in the object or living organisms, and includes an identifying code and a reader for reading this code.
  • The micro chipp in your pet is a tiny implant, about the size of a grain of rice, which your vet injected painlessly under the skin.
RFID Impant-Transponder

How does RFID work at petWALK?

  • Once the petWALK pet door recognizes your cat or dog and access control is enabled, the built-in RFID reader is turned on and the RFID antenna is activated in the middle of the door leaf.
  • The microchip in or on your cat or dog has no battery, but is powered by the antenna in the petWALK petflap with energy.
  • Once the chip receives enough energy, it starts transmitting his identification as a radio station on a certain frequency.
  • The petWALK animal door is listening now for about 10 seconds (orange flashing lock icon) on that frequency, and once it detects a known chip, opens the door.

How to use RFID access control

  • The following video explains how to activate and setup the RFID access control.

Possibilities and limitations of RFID

  • The petWALK pet door is compatible with all standard animal identification chips in accordance with the ISO standard 11784/11785 FDX-B.
  • However, this technology dates back from the 70s and has been standardized almost 20 years ago (1996). It is hopelessly outdated and has a number of annoying limitations. Nevertheless it is normally enough to use such implanted chips as a key for the petWALK flap.
  • However, as a pet door manufacturer we have no influence on the quality of the transponder in your cat or dog and therefore can't give any warranties with respect to the function or range.
  • We therefore recommend to test with your own pets if detection range is sufficient before installation. Shouldn't it be possible to learn the tag or the distance too limited, it is not a malfunction of the device, but a technical limitation of the ID chips.

How far is the detection range?

  • The typical reading distance of well-tuned implanted chips is approximately 10 cm up to 20 cm. The included small colar tags should provide a reading distance of at least 15-25 cm, the big transponders at least 20-30 cm. In learning mode, the distance usually is half the normal reading distance.
  • The actual achievable range is dependent on many factors. The biggest challenges are the power supply of the transponder, the transmission frequency and the position of the transponder towards the antenna.
  • On the first point, there are legal provisions, how much energy is allowed to be sent by the antenna without interfering with other electronic devices EMV standard). Depending on the quality of the chip in or on your pet it needs more or less energy to activate itself. If it needs more energy it need to get nearer to the antenna. The principle is called inductive coupling. The distance between the two coils is the wireless transmission link and should be minimized. The greater the distance of the two coils the flux leakage is massively increased, so that the inductive coupling is reduced and the efficiency deteriorates. Typical distances, which can be bridged by this method are approximately the coil diameter up to twice the coil diameter. The coil diameter of the transponder in your pet is only a few millimeters, so the theoretically achievable distance is also limited to a few centimeters. This is also the reason why the much larger compared collar tag works so much better.
  • The second challenge is the correct transmission frequency. Although this is defined in the standard and the petWALK pet door adheres very closely to it (it is adjusted daily). But specially implanted chips often exhibit considerable variation, which means that they do not send on the agreed frequency. One can imagine as if you were listening to a radio program with a mistuned radio. There is noise and you can hardly hear anything. Only when the signal becomes stronger, which means your pet gets closer to the antenna, one can recognize the data.
  • The third factor is the position of the transponder in the electromagnetic field. This means, as the chip that looks like a grain of rice, is aligned with the antenna in the door leaf. It works best when it stands normal to the door leaf and very poor when he is in a parallel position. This has physical reasons (magnetic field of coil) through the construction of the implanted transponder. This fact has a dramatic impact on the read range of works great not to.
  • To maximize the reach petWALK doe not read the numerical value of the chips, but analyzes the frequency spectrum of the chip by means of complex mathematical methods and compares it with previously stored patterns.
  • The range of the chip can not be changed on the door.

What should you look for when implanting?

  • Positioning:
    Typically, an identification chip is implanted by a veterinarian into the left neck. For use with a petWALK pet door it would be beneficial if this were as far forward as possible closely behind the ear. It is also helpful if the veterinarian injects the chip in a way that it lies horizontally. That way the chip can absorb most of the energy and can start sending earlier.
  • Implant:
    We recommend to test the microchip prior to implantation at our door. It should be noted that the chip is in the syringe very well shielded by the metal needle. If, however, the syringe with the tip forward moved toward the door leaf, the chip should be able to be detected in 3-5 cm distance. If successful, the chip will work in the animal body before our pet door. Of course, you pet might still have to practice a bit to get to the appropriate part of the body as close as possible to the door. Usually your pets are quite smart and learn very quickly. The range depends on the quality of the transponder. Usually transponder from brand manufacturers such as by Virbac of "Back Home Biotec" work very well.