2-1
The basic 4020 Fire Alarm Control Panel is comprised of four assemblies:
•
Master Controller
(Part No. 565-325)
•
Standard Slave
(Part No. 565-368 for Universal Supply installation
565-222 for Intelligent Supply installation)
•
Power I/O Interface (Part No. 565-256 for Universal Supply installation
565-220 for Intelligent Supply installation)
•
Power Supply
(Part No. 636-341 for Universal Supply installation
636-289 for Intelligent Supply installation)
The Master Controller PCB assembly is responsible for overall 4020 system
supervision and control. The Master Controller communicates with other
system sub-assemblies over a two-wire RUI signal interface.
Certain interactions between the Standard Slave and Power I/O Interface boards
are necessary so that system power can be properly initialized. Once this
initialization occurs, the Master Controller to can perform supervisory functions:
•
With +5V power initialized, the Master Controller can supervise
the panel keypad and display operation status.
•
With +28V power, the Master Controller can use its
communications interface to supervise system status and control
signal circuits in the event of an alarm condition.
The status of Monitor, NAC, Mapnet and Power Supply circuits is polled and
reported back to the Master Controller upon demand. The Master Controller
evaluates Slave card information and initiates signaling devices when an alarm
condition is detected.
The basic system Standard Slave card controls power supply initialization. It
then supervises and controls I/O circuits at the command of the Master
Controller.
The Standard Slave also supervises a Mapnet channel. On power-up each
microprocessor initializes independently.
There are several possible problems that can interrupt the Standard Slave cards
initialization process and cause the system to hang. For details of the Standard
Slave initialization process refer to Chapter 5; “Standard Slave Software
Initialization”.
Continued on next page
Chapter 2
Basic System / Sub-Assembly
General Description
Master Controller
Standard Slave Card
