iPulse iPB4, Руководство пользователя

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iPB4 Biometric Device Range – Installation & User Guide – Rev 07 ©2017-2018 iPulse Systems
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PRINCIPLES OF ACCESS CONTROL
Since most biometric readers are used to manage access in secure areas, it is considered good practice to
ensure that all readers are powered from separate battery backup units. This way, in the event of a power
failure of some kind, only 1 or perhaps 2 devices are affected, rather than the entire setup.
With PoE, if the one central switch goes down, it can take down not only the communications, but the
function of the access control units, across an entire wing or even an entire building.
MANAGING DEVICES
Another major disadvantage of biometric installations is that they tend to be connected to other devices
such magnetic locks, striker locks and similar.
These devices tend to draw far more current than the biometric reader does, and most often, put
significant strain onto the maximum allowed amperage being supplied by the device.
Experience has shown that whilst certain custom-made midspan devices can supply this current, their
longevity is extremely poor, probably given that they do not follow the standards laid down for the
maximum supply of power over Ethernet cables.
It is therefore critical that anyone using iPulse biometric devices with PoE should take great care to only
use the recommended products to avoid issues with the continued successful operation of the system.
LIGHTNING AND CURREN T SURGES
In addition to the above, devices connected directly to the power supply are more susceptible to over
voltage damage than those devices connected via a battery backup power supply, as the chances of the
cable transmitting an overvoltage event such as a lightning strike are exponentially increased as the cable
length increases.
USING POE WITH IPULS E BIOMETRICS
The iPulse iPBX range of biometric products currently does NOT natively support PoE, however, an updated
IntelliRelay is expected during the course of 2018 that should support this.
However, in environments where the biometric reader is being used in isolation, such as a time and
attendance reader NOT connected to any other devices, the use of PoE is possible, and extremely simple,
if required.
CABLING AN IPBX READ ER TO WORK WITH POE
All the iPBX readers (with the exception of the iPB1 and iPB8 devices) are powered via the IntelliRelay. This
device traditionally receives 13,8 V DC from a battery backup, and translates this power into that required
for the reader.
In order to connect an iPBX reader to a PoE Ethernet cable, the best option is to purchase a splitter (also
known as a “picker” or “tap”) which can be attached to the end of the PoE Ethernet cable sitting in the
ceiling.