One of the aims of a designer of an entry-point unit for an access control system must be to keep it as unobtrusive as possible. IE Keyprocessor has certainly achieved this with the SL-4 reader and even included an element of disguise. Had the reader been slightly larger, no doubt regular attempts would be made to deliver the mail through it! Access is gained by placing a coded key in the guidance slot and sliding it across the face of the SL-4 reader. A single red LED can be used to indicate successful access/refusal/reading error. Reading error should not be a problem with the SL-4 since it uses Hall Effect sensors which can cope with a wide range of swipe speeds.
The SL-4 connects directly with a custom-built IE Keyprocessor Orbit reader interface but it can also be used with other interface modules providing that they use the same clock and data interface protocol.
Construction
The SL-4, measuring 158 x 52 x 15.5mm, has a one-piece stainless steel casing which is interrupted only by the LED opening. The casing includes the key guidance slot which, at 22mm wide and just 3.5mm deep, is not likely to be jammed by vandals.
The base is of toughened plastic and the whole unit (case, base and internal electronic components) are potted and stuck together using a synthetic resin. The result is a very solid, impervious unit, which the manufacturer has given an index of protection rating of IP 68 – the highest! The six indicates complete protection against contact with live parts and ingress of dust, while the eight indicates protection against indefinite immersion in water at a specified pressure. So there should be no worries in almost any environment – maybe except direct lightning strikes! Cable entry is at the rear and two M5 threaded sockets are included for mounting purposes.
The reader is very neat and unobtrusive. The only vulnerable part is the LED, which could be disabled with a blow from a pointed tool.
The keys, measuring 70 x 21.5 x 2.7mm thick, are nickel plated and weigh approximately 20g.
This is not excessive for a key. A hole is cut in one end to form a loop, for hanging on a bunch of keys, offset at an angle to enable the key to be held flat against the surface of the reader in the guidance slot while still attached to the key-ring.
The operator is assisted in this action by magnetic attraction between the key and reader. The magnitude of this magnetic attractive force is large enough to hold the key attached to the reader unsupported.
The key is backed with an insert of plastic. This prevents metal-to-metal contact between key and reader, reducing friction and wear, and also contains the magnetic code. The 48-bit magnetic code is set by the manufacturer to include a four-digit system identification code and a four-digit key code. Each key has its own number lightly etched on the surface so that they can be readily identified.
Installation
The SL-4 reader is intended to be bolted through the wall of the premises, using the two 120mm long M5 threaded rods, nuts, washers and embellishment caps provided. An additional hole is needed for the cable. The result should be a very neat installation.
The SL-4 is supplied with 2.5m of seven-core screened cable attached. This can be extended to a maximum of 20m if required.
If bolting through the wall is not possible, as would be the case when mounting on a cavity wall, then an aluminium external mounting plate is available.
IE Keyprocessor provided two diagrams on a single A4 sheet, one showing the cable cores of the SL-4 and the other showing its connection to its Orbit universal reader interface. Some confusion occurs here because the SL-4 diagram shows no connection to the cable screen and yet the reader interface diagram shows a terminal for a screen, marked 'shield'.
Cutting back the sleeve on the end of the SL-4 cable exposes a brown lead soldered to the cable screen and taken to the GND connection making three cores soldered together at that point, brown, brown and white. The cable screen is therefore connected to the GND terminal on the reader interface module.
To add to this confusion there is not a terminal for the load (blue) connection, which is obviously superfluous in this application.
The manufacturer's technical support engineer is taking action to make the situation clearer.
Instructions
The information supplied included installation instructions and a technical specification, accompanied by the diagram sheet. The instructions are clear and adequate.
What the manufacturer says ...
IE Keyprocessor has, over the past 20 years, dedicated itself to the development and design of hi-tech robust access control products. The development of the SL-4 reader goes back to the Eighties when three Amsterdam students entered a competition. The project was the famous White car project which required controlled access to energy-saving vehicles.
The development of the project came under the three R structure – Read, Release and Return. Those three students won the competition, and this was the first real opportunity for IE Keyprocessor to develop and design a product that had no original specification, it was all down to market research. The rest is history.
The SL-4 Stainless Steel is in widespread use throughout the world and offers a robust sensible solution for applications that require a durable and user-friendly interface. The secret to the SL-4 reader is the unique IE Keyprocessor key, which is designed to be carried on a keyring and is read by sliding it across the reader.
The SL-4 is ideal for use in areas of high risk. Its coding system is based on a magnetic code. Unlike with credit cards, this code is not written on the surface but is embedded inside the protective material.
The reader itself is slimline and consists of a stainless steel plate with a slot that guides the keys. The SL-4 is equipped with a LED which indicates whether access is granted after reading the code on the key. The data consists of a four-digit system code and a four-digit key number. The SL-4 electronics are totally encapsulated in a special synthetic resin, making the unit an ideal choice for use in harsh environments. It comes complete with 2.5m of cable as standard. This can be extended to 20m.
Overall Assessment
This is a well designed, neat and robust portable key access system, highly resistant to vandal attack and almost impossinle to jam. Being sealed in synthetic resin, it has the highest IP rating and should withstand harsh enironmental conditions. They keys have individual magnetic coding and identification. They are designed for hanging on a keyring and are easy to use, being held limpet-like on the reader when properly placed in the guidance slot. Installation is straightforward.Source
Security Installer
