IP Access Control - Locking up Your Security

In this, our final entry about IP-based Access Control we will examine the locking devices that secure the doors and respond to the systems commands.

To recap what we have already covered: with an IP-based reader, such as an Isonas Power-Net reader, there is no need to install and wire a control panel. Since each reader has an IP connection, all intelligence is right there at the door. A host Windows PC running Crystal Matrix software manages the system. Once the administrator has customized the desired access control, Crystal Matrix sends the information to each of the readers so all entry requests can be processed locally.

No power wires are needed either since the reader can use Power over Ethernet (PoE).  Each reader can then be equipped with a data/power pigtail connection so that it can connect to the door for input from the proximity access card and relay output to control its locking device.

Strikes and Locks

No, this is not a new variation of baseball. Strikes and locks are locking devices.

Electric Strikes

An electric strike only controls the entry side. Upon exit, the door can be freely opened. Like a fixed strike found in a standard lock, the electric strike presents a ramped surface to the latch so the door can close and lock.

There are two types of electric strikes.

•         A Fail-secure strike, also known as fail-locked or non-fail safe requires electric current to be applied to it in order to open. Power can be either AC or DC, with DC offering silent operation except for a click when the lock releases, and AC causing the unit to buzz. Should there be a power failure, the strike would remain locked from the outside but as noted the knob or handle can always be turned from inside the facility to allow egress.
•         Fail-safe, also known as fail-open is just the opposite,  requiring electrical current to be applied to the strike in order to lock. Fail-safe strikes run only on DC power, and in the case of a power failure the door could be pushed or pulled open.

Whether the electric strike is fail-secure or fail-safe, it is important that the lock require no more than 500ma of current in order to allow the reader to be powered over Ethernet.

Magnetic Locks

A magnetic lock consists of an electromagnet attached to the door frame and an armature plate attached to the door.

 A constant electric current passes through the electro-magnet so that it is magnetically attracted to the armature plate, in effect, keeping the door locked until the reader interrupts the current. Since an access card must be used on either side of the door, magnetic locks are ideal in high security facilities that keep track of when a user enters and when he exits. Every request to open can be stored on the Crystal Matrix data base.

Locks on exterior doors can require higher magnetic force while those on interior doors could require less. In order to maintain safety, auxiliary power supplies should be installed in a fire panel so that the locks can be released in an emergency.

Knock Knock. Who's There?

It's great to know how the IP reader communicates with the locking device but how does it know who's "a-knocking" to get in?

That would be by means of a proximity device credential used for identification. This device might be a thin card, a key fob, a clam shell, or a cap tag. See Making Access Control Easier, part 2 for an explanation of each of these.

But how does the reader actually read the information stored on any of these? 

RFID stands for Radio Frequency Identification and is a wireless non-contact system used for identification and or tracking. Electronic tags store the data and transmit it to readers using radio-frequency electromagnetic fields. RFID can use kilohertz, megahertz or gigahertz wavelengths. Isonas credential tags and the PowerNet reader-controller communicate at 125 KHz.

RFID is ideal for access control since it works rain or shine, in heat and cold, in bright sun-light or dusty air. Neither batteries nor pin codes are needed, and each credential’s ID holds unique information. All the bearer has to do is present the tag within a few inches of the reader-controller and wait for the electric strike or magnetic lock to release.

We cannot leave access control without considering emergency situations. In most states, fire codes require some sort of over-ride device to allow a quick exit. One solution is to install a Request to Exit (REX) button.


A REX button is particularly necessary with a magnetic lock which requires reader-controller permission on both sides of the door. A REX button, installed on the exit side of the door and fitted with a pigtail and hooked up to Ethernet cabling, when pushed would automatically open the door.

If you are ready to use your existing IP network for real-time control of your facility's security, visit www.kintronics.com to see your options or call 1-800-431-1658 to speak to a Kintronics sales engineer who can tailor a system to fit you needs.Or if you'd prefer simply fill out this information request form for a quick response.