Backup batteries for access control

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If the power is out you want to keep your doors locked. That's where backup batteries come into play. Sometimes the building provides them but typically they are installed in combination with every larger access control system as an extra layer on top. Typically the batteries will make sure to provide extra 24 hours of backup power to keep everything safe and secure while there is an outage going on. 

Altronix backup battery

Low voltage supplier Altronix provides the most used backup batteries in the access control market. They get continuously charged but when supply stops, they can hold power for up to 24 hours.

Kisi's opinion: While it's great to have a backup battery in theory, in real life it can also be a big burden especially if the system is not designed well. You need to make sure the doors can still unlock even when there is only backup power running.
‍‍Altronix backup battery
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What are RFID key cards?

RFID cards are most widely used in commercial office spaces. These cards (or tags or fobs as they are sometimes referred to) can be classified by the range they communicate (low, high or ultra high) and the way the communication happens with the reader (active or passive).

How are permissions encoded on a magnetic key card?

Each key card system comes with a key encoding machine, which will configure the permissions granted to your card. The system should allow you to grant permissions for multiple doors, configure date and time for access, and even the number of times a user can access the space.

All these details are built into a very complicated algorithm which is written unto your key car’s magstripe. This magstripe contains thousands of tiny magnetic bars, each which can be polarized either North or South. Polarizing these magnets creates a sequence that is encoded on your card. 

There are other ways to encode a key card, but those are usually used for corporate spaces. These include newer models that have radio-frequency identification (RFID), or “smart cards” which contain an embedded micro-controller to handle security. RFID key cards will be covered below.

Your RFID reader can operate on different frequency ranges:

- Low Frequency (LF) RFID operates around 30 KHz to 300 KHz and have a maximum range of 10cm. Your conventional office access cards usually utilizes LF range.

- High Frequency (HF) RFID operates around 3 MHz to 30 MHz and provide distances between 10cm and 1 meter. Examples of access cards that uses HF RFID are NFC cards.  Smart cards like MIFARE are also based on this standard.

- Ultra High Frequency (UHF) RFID ranges between 300 MHz and 3 GHz and reads up to 12 meters. They are typically used for parking solutions or similar wide range applications. 

Now that we covered the different types of RFID frequency, there is another parameter to consider. RFID can be distinguished into two broad categories: passive or active tags (or cards). 

- Active RFID tags have their own transmitter (and power source). Active RFID tags are used for cargo, machine or vehicle tracking.

- Passive RFID tags do not require a battery. The reader on the wall sends a signal to the tag. That signal is used to power on the tag and reflect the energy back to the reader.

These proximity cards are low frequency and mostly fall under the category of passive RFID cards.

How do RFID key cards work?

- Passive cards have three components sealed in the plastic: an antenna (mostly coil of wire), a capacitor and an integrated circuit (IC) which contains the user’s ID number.

- The RFID reader on the wall has an antenna which continuously emits a short range Radio Frequency (RF) field. 

- When you hold the card on the reader, the card absorbs the energy from the RF field generated by the reader. This energy is creating a current powering the integrated circuit which in turn makes the chip emit its ID number.

- The reader checks sends the ID back to the server closet or IT room, where the main access control system panel usually resides. The sent ID signals that this user wants to unlock the door. The format the reader communicates is often using the Wiegand protocol.

DID YOU KNOW: RFID technology is being used on credit or debit cards as well, creating a contactless form of transaction.

Types of HID cards

HID Indala is a great access card for advanced needs in access control and security. 

Types of cards

- CX Series CASI Compatible Prox Credentials

- FlexISO Imageable Card

- FlexISO XT Durable Composite Card

- FPMXI FlexPass MIFARE / Indala Combo Smart Card

- FlexCard

- FPDXI FlexPass DESFire / Indala Prox Combo Card

HID's iClass SE Seos ID card

HID's iClass Seos ID cards are due to their "SIO" (Secure Identity Object) enablement one of the more secure cards. 

They are typically used with UHF (Ultra High Frequency) applications such as for gates or garages.

iClass SE runs on 13.56 MHz but can be used in "dual technology" mode essentially incorporating 125 KHz Proximity.

- 3350 iCLASS SE Clamshell Card

- 600x SIO Enabled UHF Card

- 601X SIO Enabled UHF/iCLASS Card

- 300x iCLASS SE Card

- 310x iCLASS SE + Prox Card

- 325x iCLASS SE Key Fob II

- 340x - MIFARE Classic SE Card

- 350x SIO Technology-Enabled MIFARE + Prox Card

- 370x - MIFARE DESFire EV1 SE Card

- 38xx SIO-Enabled MIFARE DESFire EV1 + Prox Card

KISI iClass is the top model of HID Global. It is available in 2k bit (256 Bytes), 16 bit (2K Bytes) or 32k bit (4K Bytes) configurations.

HID's iClass ID card 

HID's iClass badges are MIFARE Desfire EV1 or MIFARE Classic based cards - in part also with prox backwards compatibility.

  • 232, 242 & 243 iCLASS + MIFARE Classic or MIFARE DESFire EV1213x iCLASS Embeddable & iCLASS Prox Embedded Card
  • 252, 262 & 263 iCLASS + MIFARE Classic or MIFARE DESFire EV1 + Prox202x iCLASS + HITAG2 Card200x iCLASS2080 iCLASS Clamshell Card
  • 202x iCLASS + HITAG1 Card202x iCLASS + Prox Card HID's Prox ID card HID Prox is an entry level keycard for getting started with access control or basic needs. Types of cards 1386 ISOProx II Card 1326 ProxCard II Clamshell Card 1336 DuoProx II Card 1351 ProxPass II Active Tag 1597 Smart ISOProx II Card 1598 Smart DuoProx II Card HID's FlexSmart, MIFARE, DESFire ID card HID's FlexSmart badges are MIFARE or DESFire compatible. 
  • Types of cards 1451x SIO Solution for MIFARE DESFire EV1 + HITAG1 Card 1431 MIFARE / HID Prox Combo Card 1455 DESFire Tag FPMXI FlexPass® MIFARE / Indala® Combo Smart Card 1450 MIFARE DESFire EV1 Card 1451 MIFARE DESFire EV1 / HID Prox Combo Card 272, 282 & 283 MIFARE Classic solution + MIFARE DESFire EV1 solution FPDXI FlexPass® DESFire / Indala® Prox Combo Card 

ID Card Wholesellers

Identicard not only sells ID card but also software like PremiSys. It allows to grant and restrict access to doors, lock down facilities, view integrated video, create detailed reports and more.

Popular blank cards

Standard ID cardsProximity CardsSmart CardsBadge Buddies / role - recognition cards

Give your organization a simple, professional badging solution with a variety of customizable PVC and Teslin® substrate identification cards.

ID Card Group offers a full line of ID card equipment, supplies, and accessories – from identification and access control products, to promotional products for loyalty or membership programs, to gift, payment, or phone cards and systems.

Popular blank cards

HID Prox & HID iClass—The gold standard in access control technology offers a wide range of prox credentialsGeneric Brand—Low-priced alternative to brand-name credentials can be used in your existing access control system XceedID—Emerging industry leader in compatible proximity credentials (Formerly Schlage)Indala—FlexSecure proximity cards and fobs are manufactured by HID GlobalCASI-Compatible—CASI-Compatible prox cards by Indala work with CASI ProxLite Readers.Keri Systems—For Keri Tiger Controllers, IntelliProx 2000, NexTreme (NXT) and Pyramid Series Readers. 

AlphaCard has been a trusted provider of secure ID solutions since 1998. As one of the largest photo identification solution providers in the USA, we inventory over 98% of the product we ship in our own warehouse. 

Standard Blank PVC Cards, CR80Blank Color PVC Cards, CR80 30mil - 100

Hi-Co Magnetic Stripe Blank PVC Cards, CR80 30mil - 100 / 500 countStandard Blank PVC Cards, CR80 30mil

Alphacard offers ID card printers and supplies from industry-leading companies such as Magicard, HID / Fargo, Zebra, Evolis, Datacard, and many more


Key Fobs

A key fob is a type of access badge or security token. It acts as a wireless remote control device that allows users to access their buildings, offices, and cars. Such key fobs are usually utilized for locations with regular human traffic but requires entrants to authenticate their access, and it does that by initializing the built-in security access system each time the fob is activated.

Key fobs are used in apartment buildings, condominiums, offices and buildings worldwide, which often contain a RFID tag. It operates similarly to a proximity card, where they communicate access credential information (via a reader pad) with a central server for the building. Key fobs can be programmed to allow time restricted and location restricted access to permitted areas.

Locking and unlocking a door with a key fob usually only requires you to push a button on your fob. Some key fobs provides two-factor authentication where an user has a personal identification number (PIN), which authenticates them as the device's owner.

Key fobs are an integral component of keyless entry systems, especially in the automotive industry where they are used to unlock your car door from a distance. However, it still requires a physical object to be issued to users before they can begin electronically unlocking their doors. This means that losing your key fob is still a very real possibility that would prevent you from accessing your space, and undermine the security of your building or car.

How Does a Key Fob Work?

The key fob (or wireless remote) operates in conjunction with an electronic lock (e.g. an electric strike) for it to work. Most key fobs sends signals to an intermediary security access system, which in turn relays an instruction to your door to lock or unlock it.

A key fob communicates with the locks in your access control system using radio wave signals, or RFID technology. Here’s how it works:

Both the key fob on your keychain and the access control system have memory chips that allow the fob to work. When the button is pressed on the fob, it sends a code to the door with the instructions as to what the door should do, whether that is to lock or unlock the door. If the code sent to the access control system matches, it will perform that action and unlock the door. The code is randomly generated each time the fob is used.

This code utilizes a 26-bit wiegand protocol put when communicating instructions from the fob to the system. It is a binary code with 256 different possible combinations per fob, and there can be up to 65,535 ID numbers that would work for each code. Matching each code with each ID, you can issue up to 16,711,425 fobs without ever duplicating a user. Programming the key fob is essentially making sure that the access control system and the fob are synchronized so that the door would recognize the codes the fob is sending.

The frequency of the transmitter determines the maximum distance that will allow the key fob to send a code to the door. Quick note: if your fob only works when you get near the access badge, it might be utilizing a simple coil e.g. a 125kHz "transmitter". Therefore, it only works near the transmitting coil as the magnetic field decays very fast.

For more information:

Access Control Guide Table of Contents

  1. Hardware and Security Components of Access Control Systems

  2. Access Control System Technologies

  3. A Guide to Office Security

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