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Section 2: System Overview
Section 2: System Overview
Section 2: System Overview
Section 2: System Overview
Section 2: System Overview
2–1
2–1
2–1
2–1
2–1
N-1000-III/IV
N-1000-III/IV
N-1000-III/IV
N-1000-III/IV
N-1000-III/IV
Section 2: System Overview
2-1: N-1000-III/IV
The N-1000-III/IV control panels are the decision-making units in the access
control system. Each control panel contains a central processing unit (CPU) and
memory for local control capability. Control panel database information is
programmed from a central programming device (computer, printer/programmer
or data terminal). The panels then operate independently from the
programming device. In this distributed database system, the programming
device need not be on-line for system operation.
The control panels interface to the programming device via the C-100-A1
20 mA Current Loop Converter or via the 485 multi-drop interfaces
(N-485-PCI-2 or N-485-HUB-2). A single communications loop supports up to 63
uniquely addressed control panels if the 20 mA loop is utilized or 31 panels for
485 communications. A typical 20 mA communications loop configuration is shown
in Figure 2-1, while Figure 2-2 illustrates a typical 485 multi-drop
configuration.
The N-1000-III control panel provides 16 points for alarm monitoring and four
output control relays. The N-1000-III-X control panel includes four additional
relays (providing a total of eight) and has expanded database/buffer memory
capacity. The N-1000-IV version has four rather than two card readers and four
output control relays. The N-1000-IV-X control panel includes four additional relays
(providing a total of eight) with expanded database/buffer memory capacity. The
N-1000-IV
N-1000-II
N-1000-III
Personal Computer
C-100-A1
-
Figure 2-1.
Typical 20 mA Communications Loop.
The N-1000 control panels can be in
any order in the loop or dropline as long as each has a unique address.