DIY: RFID Security Kit Project
Take Security into Your Own HandsBy Robert Cong
Description: Velleman RFID Kit (MK179)
Assembly Time: 1 to 2 hours
Skill Level: Beginner
Radio frequency identification (RFID) is a technology that has been around for quite some time, but its wide spread use has been on the rise in recent years. Credit cards, time clocks, and toll booths are just the few of the many applications that have made use of this technology. With this kit, you can add a high-tech spin to some of your daily tasks.
Parts Used in Project:
9V battery snap-on holder
Wall adapter (12V, at least 100mA)
Step 1: Solder All ComponentsGet the Velleman RFID kit and solder all the parts according to the instructions provided. Each component placement is labeled on the board so you should have no trouble finding the correct spot for each part. The components with polarity are the diodes, transistors, ICs, voltage regulator, the LED and electrolytic capacitor, so make sure these components are placed correctly on the board or the kit will not function properly.
Step 2: Measure Length of WireOnce all the components have been properly soldered in place, determine how far you want the RFID reader to be placed from the kit. According to the instructions, the maximum distance is five meters (about 16.5 feet). This depends on your application. Here, I used 22 inches of wire for demonstration purposes. Take your wire and solder the PCB tabs to the coil in the correct configuration as shown below.
Step 3: Designate RFID TagsThe instructions to designate the tags are included with the kit, but let's run through the process quickly. The kit comes with two Velleman RFID tags (the kit will respond to all Velleman HAA86C/TAG(2) tags). When designating the first tag, you will also set the pulse length. Up to 25 different tags can be stored on one unit. To designate the first tag:
1. Power the kit with the AC adapter, then press and hold down the switch button.
2. Hold a tag within the proximity of the coil. The relay will pulse twice to let you know that the tag has been stored.
3. The relay will then pulse every second to indicate the length of pulse you wish to set. You can set the pulse up to a maximum of 240 seconds (four minutes).
4. The button must be pushed until the relay has pulsed at least five times.
5. Release the switch button
6. Now every time this particular tag is held within proximity of the coil, the relay will pulse for that specified length of time you indicated.
Step 4: Apply PowerIt's important to keep in mind that the kit does not transfer power through to the output. You will need another power source for your application, but keep in mind that 24V/3A is the maximum output that can be connected to this kit. The wall adapter power source I decided to use is a 12V, 1A regulated wall adapter with a 2.1mm plug on the end. Since the kit comes with terminal block connections, I cut off the 2.1mm plug and directly inserted the leads into the terminal. On the output, I use a 9V battery with a 9V battery snap-on holder to power the LED module.
There some common confusion with the relay output connections, which are noted as "NO"-Normally Open, "COM"-Common, and "NC"-Normally Closed. Connect to COM and NO if you want the circuit to be on when the relay coil is on. Connect to COM and NC if you want the circuit to be on when the relay coil is off.
ApplicationsThat's all you need in order to have your very own security light sensor. Just mount the ID tag onto a door and configure it so that when the door is opened, it must pass through the proximity of the coil. Once the door is pushed open, the RFID kit will send the pulse through to output and power the LED module to shine brightly upon any would-be intruders. You can use this on outside of your home as a security light, or inside your home for catching nosy people peeking into your room, or just as a power saving nightlight which will power on only when you want it to, instead of all night long. If one of these incredibly bright modules is not quite enough, keep in mind that you can link up to 30 of them together for one very bright spotlight.
You can also use this kit as a small door opener, such as a pet door. Just hook up a DC motor to the output of the kit and set the pulse length accordingly. You can place one of the tags on the collar of your pet and teach it to move within the proximity of the coil in order to get to the backyard and take care of its business. It can also be used for unlocking regular-sized self-latching doors. Simply configure the kit so that the pulse will unlatch a door for a specified period of time. Set it up so that once the self-latching door is closed, the pulse will be over and a new tag must be within the vicinity of the coil in order to be unlatched again.
With the kit being just 2.6" x 2.3" in size, it's small enough to be placed almost anywhere while staying discreet, allowing you to widen the possible number of applications.
ConclusionRFID technology is a very convenient way of making processes much faster and simpler. To learn all the basics of RFID technology and program your own personal settings, check out the RFID design lab.
Leap Electronic RFID Design Lab
There are plenty of possible applications with this small Velleman RFID kit. The more you play with it, the more ideas come to mind. Just make sure to keep it away from moisture. You can do so by placing the kit in an enclosure. Also, if you decide to use it with the LED light module, be nice and try not to blind anyone; it's super bright.
Robert is a graduate from Cal Poly, San Luis Obispo in Electrical Engineering. He is originally from Lincoln Heights in Los Angeles, CA, and currently resides in Belmont, CA where he works as a Technical Copy Writer/ Product Manager for Jameco Electronics. His interests include sports, movies, music, and playing with cool, new gadgets.