Installation guide

10 en | Installation with RS-485, AMC and Access PE Access Control by Example
| 1.0 | 2009.10 Introductory Guide Bosch Security Systems
3 Installation with RS-485, AMC and Access PE
This chapter describes the installation of our example access control system using RS-485
communication to the readers, an AMC2 as access controller hardware and Access
Professional Edition as the configuration software. We will assume that all the components
decided upon in Section 2.2 Low tier: Electrical components, page 6 have been ordered from
and delivered by the hardware vendor of your choice. The installation is basically a 6 stage
process:
1. Mounting the access controller and associated hardware, see 3.1
2. Installing the wiring, see 3.2
3. Mounting the peripheral components, see 3.3
4. Connecting the peripheral components to the wiring, see 3.4
5. Connecting the AMC to the wiring from the peripheral components, see 3.5.2
6. Connecting the AMC to the computer and configuring the software, see 3.5.3
3.1 Mounting the access controller and associated hardware
The obvious room in which to locate the access controller, the power supply and the
configuration PC is the office. In it the hardware and software will be protected from
unauthorized access. The office is also situated centrally with regard to the doors. The
controllers should be housed in a lockable metal enclosure or cabinet for extra security. The
enclosure should also contain a battery to provide an uninterruptible power supply (UPS).
3.2 Installing the wiring
Lay the cables decided upon in Section 2.2.3 Wiring for non-reader components, page 8 from
the office to the respective doors. Aesthetically it is always preferable to hide cabling beneath
floors, above ceilings or underneath wall plaster, but this is not always practical. Note -
junction boxes are commonly used near doors; we leave them out of this example only for the
sake of simplicity.
Make sure that cables carrying data (e.g. from the reader) are shielded, see 3.4.2
Make sure that there is enough length to reach both components above the door (e.g. REX
with motion detector, magnetic contacts) and components at handle height (e.g. reader, door
opener).
3.2.1 RS-485 bus topology for readers
Readers in an RS-485 environment are connected in a bus topology, i.e. a reader is either
connected directly to the controller and to the next reader, or it is connected to the previous
and possibly the next reader as part of a chain with a maximum length of 4 readers. See
Section 2.2.1 Card reader technologies, page 7.
With readers it is very important to follow the manufacturer’s instructions as regards
grounding (earthing) the device and its cable shielding. See also Section Figure 3.3 Avoiding
a ground loop, page 12
3.2.2 RS-485 star topology for all other components
Every other component in an RS-485 environment is connected directly to its respective
controller in a star topology.
3.3 Mounting the peripheral components
Electrical components must always be mounted (i.e. attached to walls, racks, doors and door-
frames) as per the manufacturer’s instructions.