Zerksus 4 Port Access Controller (Not yet ready for ordering)


Please note that we temporarily stopped this project. This is truly a wonderful product but it is so feature packed that it actually scares off clients, due to its complexity. You need good IT skills to install it and we found that if the same person cannot do both the installing/wiring AND the IT side that you have lost the game. Also, most clients rarely have an application for more than 1000 cardholders. This makes the 1 000 000 card engine quite redundant, along with the multiple access methods.

Another scary problem is the fact that the unit uses a SD/MMC card for the added card numbers (above 14 000 users). Since cameras and cell phones started using these devices the access controller is at risk of people stealing the memory card for personal use.  Yes, people do these things. One company, with 2000 vehicles, lost a bundle on employees opening and using the cellular SIM cards over weekends, used in the GSM/GPS tracking system. If it is removable it will be removed. The one option is to solder a bracket over the connector and card, but that will require a new layout for a product that we are hesitating to continue with.

We will consider restarting the project if a large company (with installers, IT and call centre personnel with a solid track record) is interested in reselling and supporting it.


Minimum order quantity: 1 unit


This monster controller is currently only held up by the monster PC software that is currently still in development.

Central to the controller is a 60MHz  32bit RISC IP core on FPGA. Fundamentally it reads 4 readers (Wiegand/Clock Data), has 4 relay outputs and 8 inputs.

Apart from all the usual features like a real-time clock and RS485 communications it also boasts a SDcard slot (primarily used for MMC cards). It has 32 MB of RAM and can store up to 80 000 users without the memory expansion. When fitted with the memory card it can store up to 1 000 000 cards that can be expanded on special request to even more cards!  The real-time clock can be backed up by either a lithium battery (for long off power storage) or a SuperCap(days worth of backup). There is also a watchdog timer, to reset the controller, for slim chance of a software malfunction.


This is where the controller shines. It has built-in support for RS232, additional RS232 diagnostics for setup, RS485 (RS232 based) for multi-drop networking and 10 MBit/s Ethernet to plug directly into your LAN. The RS232 is for single controller usage, usually controlled by the reception PC. RS485 provides a private network up to 115200 bits/s between the controllers and PC. Ethernet is used for ease of installation and integration. In Ethernet mode you can ping and telnet a controller. This makes life much easier during installation and fault finding. The latest version of software allows you HTTP into the controller (password controlled) using IExplorer. Data transfer is also a lot smoother with Ethernet and allows effective control of databases approaching 1 000 000 cards.

Future features: The RS232 interface will allow the controller to be interfaced via USB (single controller) or the Zerksus RF interface (as used on the smaller wireless reader-controller). Although the speed will be a lot slower it does minimizes the cabling.


The controller was designed for idiots and unforeseen events. I have seen many reader ports blown because of incorrect wiring and many more fuses blown because of shorts and the common "oops" effect.

Reader channels: The data and control lines of the readers are protected up to 12V supply voltage level. You can short output signals to ground or 12V without damage. You can also connect any 5V input to ground of 12V. The only, obvious, thing you have to watch out for is shorting the supply 12V to ground, but then you will trip the external power supply (not shown).

Input channels: The inputs are optically isolated. This is not full isolation as it relies on power to be looped back but does provide protection against idiotic wiring. Each input has a direct LED display, so you don't need software to test it.

Output channels: Normally the headache of such a system. The outputs can be configured for 12V normally open (striker lock) or closed (magnetic lock) , switch normally open (boom, gate) or closed (alarm loop). In the event of a short the controller will limit the current and disable the output without causing a reset or power down. You can thus short out channel 1 while channels 2 to 4 operate normally. Nothing like a security risk to mess up you day :-) In this case people won't get stuck or door suddenly released if something goes wrong.

Additional protection for the controller is added in the form of reverse voltage protection for the digital electronics. Also fitted is a 1500Watt tranzorb, numerous MOVs and strategically placed zener diodes.

Another output FEATURE: There is a push button switch at each relay. This allows the installer to test the output without having a reader and card database installed- a real time saver.

Controller security:

An optional tamper switch is available. This is a micro switch that monitors the controller enclosure. If activated it will immediately inform and log the operator that a controller box has been opened.

Each reader channel has an additional tamper input. This is used to inform the controller if a reader is lifted from the wall. 

Power supply: (Not shown)

The power supply is a 4A combination linear and switch mode power supply. It is designed to minimize heat dissipation that so often kills the controller or itself when in a closed box. The power is sufficient to drive the controller and 4 locks. To minimize simultaneous switching the controller will never switch more than 1 lock at a time, thus reducing the chance of an overload. The PSU is fitted with current limiting devices to protect against maximum overload.

The power supply also charges a 12V battery. It uses intelligent software to protect against damage. Batteries do get old and faulty. When it does you will probably never know about it until a power failure. Not in this case. The battery is periodically tested (4 to 6 hour test) to verify that it is in good shape. When faulty the controller/PC will report it. The software can even email a service person to replace it. Note that testing does not affect the working of the backup feature in case of a power failure.

Being a mission critical device the controller monitors several voltages and currents during the operation. The controller can sense if it is being powered from battery or mains, if the battery draws excessive current during charging, dangerous current levels during operation and several other similar conditions. All this information is made available over the power supply monitoring connector. The idea is to let you know of a potential problem before the problem becomes critical.


Controller software:

Apart from the software being capable of performing web server capabilities and doing all conceivable access control features it is also extremely expandable to provide future expansions. The PC software is capable of uploading new firmware. In the case of a major disaster during such an update the installer can easily update the firmware using tools available from Zerksus. The CPU performs about 60 000 000 instructions per second. This is required for fast access times to the databases. The databases are stored randomly and the last card must be accessed as fast as possible. If you could design an 8051 or PIC controller board it would take ages to find the last card in 1 000 000 card database (and then try to do several TCP/IP port connections at the same time).

Bottom line: The controller will be ever expanding and easily upgradeable. Don't worry about features in the final controller and PC software...it will all be there.



RS232/485: 9 pin D-type connector

Ethernet:  RJ45 industry standard. Uses standard patch cables.

Readers/Outputs/Inputs/Power/Tamper: Removable terminal blocks.

Power supply monitoring: 10 way header  


  Current price projections are currently about $700 USD. Combine that with the cost effect Zerksus Wiegand readers (other manufacturers readers can also be used) and the end result is a rugged and economical access control solution. The best of all is that the PC software will be supplied at a very low cost or even free (when purchased with a minimum number of controllers).


Available options:

Stock number Available Stock Unit Price
Standard 0 R4200 to R5000







Prices given in South African Rand.