Simplex SafeLINC 4020 User manual

574-771
Rev. A
4020 Fire Alarm System
System Troubleshooting Guide

Copyright 1998 Simplex Time Recorder Co. All rights reserved.
Printed in the United States of America.
Information in this document is subject to change without notice. No part of this
document may be reproduced or transmitted in any form or by any means,
electronic or mechanical, for any purpose, without the express written consent of
Simplex Time Recorder Company.
SYSTEM REACCEPTANCE TEST AFTER SOFTWARE CHANGES - To
ensure proper system operation, this product must be tested in accordance with
NFPA72-1996, Chapter 7 after any programming operation or change in site-
specific software. Reacceptance testing is required after any change, addition or
deletion of system components, or after any modification, repair or adjustment
to system hardware or wiring.
All components, circuits, system operations, or software functions known to be
affected by a change must be 100% tested. In addition, to ensure that other
operations are not inadvertently affected, at least 10% of initiating devices that
are not directly affected by the change, up to a maximum of 50 devices, must
also be tested and proper system operation verified.
DO NOT INSTALL ANY SIMPLEX PRODUCT THAT APPEARS
DAMAGED. Upon unpacking your Simplex product, inspect the contents of
the carton for shipping damage. If damage is apparent, immediately file a claim
with the carrier and notify Simplex.
ELECTRICAL HAZARD - Disconnect electrical power when making any
internal adjustments or repairs. Servicing should be performed by qualified
Simplex Representatives.
STATIC HAZARD - Static electricity can damage components. Therefore,
handle as follows:
1. Ground yourself before opening or installing components (use the 553-484
Static Control Kit).
2. Keep uninstalled components wrapped in anti-static material at all times.
RADIO FREQUENCY ENERGY - This equipment generates, uses, and can
radiate radio frequency energy and if not installed and used in accordance with
the instruction manual, may cause interference to radio communications. It has
been tested and found to comply with the limits for a Class A computing device
pursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide
reasonable protection against such interference when operated in a commercial
environment. Operation of this equipment in a residential area is likely to cause
interference in which case the user at his own expense will be required to take
whatever measures may be required to correct the interference.
Copyright and Trademarks
Cautions and Warnings

i
Tables and Figures In this Document................................................... ii
Chapter 1 About This Document
Introduction ....................................................................................... 1-1
Chapter Content.................................................................................1-1
Chapter 2 Basic System / Sub-Assembly
General Description........................................................................2-1
Master Controller Assembly...........................................................2-1
Standard Slave Card Assembly ..................................................... 2-1
Expansion Cards............................................................................2-2
Addressing...................................................................................... 2-2
4020 Master Controller....................................................................... 2-3
Description and Functions.............................................................. 2-3
System Block Diagram (Universal Supply) ....................................2-4
System Block Diagram (Intelligent Supply)....................................2-5
Master Controller PCB Layout........................................................ 2-6
Master Controller PCB Assembly I/O Connectors .........................2-6
4020 Standard Slave.......................................................................... 2-7
Description and Functions.............................................................. 2-7
Application......................................................................................2-7
Standard Slave PCB Layout........................................................... 2-8
Standard Slave PCB Assembly I/O Connectors ............................2-8
4020 Power I/O Interface...................................................................2-9
Description and Functions.............................................................. 2-9
Application......................................................................................2-9
Power I/O Interface PCB Layout..................................................2-10
Power I/O Connector Voltage Points............................................ 2-10
Power I/O Interface PCB Assembly I/O Connectors....................2-11
4020 Power Supply..........................................................................2-12
Description and Functions............................................................ 2-12
Application.................................................................................... 2-12
Power Supply I/O Connectors......................................................2-12
Chapter 3 4020 Problem Experience
Overview......................................................................................... 3-1
Where Problems are likely to Reside............................................. 3-1
Troubleshooting Difficulty............................................................... 3-1
General Issues................................................................................... 3-2
Problems Associated with Assembly/Dis-Assembly and Installation.3-4
Problems Associated with Power Supplies........................................ 3-6
Chapter 4 Troubleshooting Procedures
General Approach .......................................................................... 4-1
Matching Standard Slave, Power Supply and Software Versions .4-1
Master Controller Initialization........................................................ 4-3
+5V Power......................................................................................4-3
Panel Alarm Sounding and can not be Silenced............................4-4
A-tap Problems............................................................................... 4-4
B-tap Problems............................................................................... 4-5
+28V Power....................................................................................4-5
Standard Slave Initialization...........................................................4-5
36V Mapnet Power.........................................................................4-6
Troubleshooting Chart....................................................................4-7
Chapter 5 Standard Slave Software Initialization
Standard Slave Initialization Sequence.......................................... 5-1
Table of Contents

ii
Tables and Figures in this Document
Tables Table Description Page
Table 2-1 4020 System Device Address Assignments 2-2
Table 2-2 565-325 Master Controller PCB Assembly I/O Connectors 2-5
Table 2-3 Jumper Plug Color Code Scheme 2-7
Table 2-4 565-222 & 565-368 Standard Slave PCB Assembly I/O Connectors 2-8
Table 2-5 565-256 Power I/O Interface PCB Assembly I/O Connectors 2-11
Table 2-6 565-220 Power I/O Interface PCB Assembly I/O Connectors 2-11
Table 2-7 636-341 (Gold Wing) Power Supply I/O Connectors 2-12
Table 2-8 636-289 (Black Hawk) Power Supply I/O Connectors 2-12
Table 4-1 Troubleshooting Chart 4-7
Table 5-1 Standard Slave Initialization Sequence 5-1
Figures Figure Description Page
Figure 2-1 4020 System Block Diagram (Universal Supply Installation) 2-4
Figure 2-2 4020 System Block Diagram (Intelligent Supply Installation) 2-5
Figure 2-3 565-325 Master Controller PCB Assembly 2-6
Figure 2-4 565-222 & 565-368 Standard Slave PCB Assembly 2-8
Figure 2-5 565-256 Power I/O Interface PCB Assembly 2-10
Figure 2-6 565-220 Power I/O Interface PCB Assembly 2-10
Figure 2-7 Voltage Points on Power I/O PCB Connectors and Terminal Blocks 2-10

1-1
This troubleshooting guide provides you with a basic understanding of the 4020
Fire Alarm Control Panel operation and suggestions for quickly finding and
resolving problems.
The primary goal is to provide a method by which you may troubleshoot the
4020 basic system assemblies:
•Master Controller
•Standard Slave
•Power I/O Interface
•Power Supply
It is assumed that any defective system can be broken down into this minimum
configuration as the first step in troubleshooting a problem.
This document is divided into five Chapters:
1. About this Document Describes this document’s structure.
2. Basic System/Sub-Assembly Describes the 4020 system. Includes
Block Diagrams, and PCB layouts.
3. 4020 Problem Experience Describes commonly occurring
problems based on Service repair
experience.
4. Troubleshooting Procedures Provides problem indications with
their associated potential causes.
Includes a Troubleshooting Chart
(page 4-7)
5. Standard Slave Software
Initialization Describes the sequence of events during the Standard Slave Card
initialization process.
Chapter 1
About This Document
Introduction
Chapter Content

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

2-2
The basic 4020 Fire Alarm Control Panel is capable of supporting system
expansion with peripheral cards. Although not discussed further in this
troubleshooting document, the following list shows some of the supported
expansion cards:
•RS-232 Interface (Part No. 565-430) [supercedes 565-224]
•Optional Mapnet Transceiver Interface (Part No. 565-241)
•8 Point I/O (Part No.565-211)
•Contact Closure DACT (Part No. 565-627)
•Serial DACT (Part No. 565-629)
•Multiple Network Option Boards (Part Nos. 565-277, 565-411, 565-518)
Most PCB assemblies in the system are assigned addresses for communication
with the Master Controller. The Standard Slave Card SW1 address switch is set
to device address 01, but the card also responds to Power Supply address 02 and
Mapnet Channel #1 address 03. The pre-designated 4020 System device address
assignments are listed in Table 2-1.
Table 2-1. 4020 System Device Address Assignments
Address System Device
0 Master Controller
1 Standard Slave (board address setting)
2 Power Supply (software address only)
3 Mapnet Channel #1 (software address only)
4 Optional Mapnet Channel #2
5 Optional 8 Point I/O #2
6 Optional 8 Point I/O #3
7 Optional RS232 Board
8 Optional Network Board
9 Optional 4003 Voice Controller
10 Optional Mapnet Channel #3
(Master Controller OS U9 Rev 7.03 and up)
11 Optional Mapnet Channel #4
(Master Controller OS u9 Rev 7.03 and up)
12 Open
13 and
Up Additional Options (SDACT, RCU, SCU, LCD, etc.)
Basic System/Sub-Assembly,
Continued
Expansion
Addressing

2-3
The Master Controller PCB assembly supervises panel operations and controls
the front panel user interface. The Master Controller communicates with panel
PCB subassemblies via a +28V signal level communications interface.
Peripheral PCB assemblies are optically coupled to this communications
interface.
Based upon the information in the configuration flash chip (U8) the Master
Controller communicates with peripheral interface cards and directs system
monitor point supervision and signal circuit control. The Master Controller +5V
and +28V A-tap power originates on the Power I/O Interface and is daisy
chained through the Standard Slave card.
The Master Controller:
•Includes main 80196 microprocessor and memory
•Processes data from all other 4020 sub-assemblies
•Controls operator keyboard, piezo alarm and display interface
•Provides a programmer interface for downloading configuration changes
•Includes city circuit interface and contains a dry contact trouble circuit
•Contains communications circuitry to Slave cards and LCD Annunciators
Continued on next page
4020 Master Controller
Description
Master Controller Functions

2-4
KEYPAD/LEDs
LCD DISPLAY
MASTER CONTROLLER
(565-325)
P1
P8
P2
STANDARD SLAVE
(565-368)
POWER I/O INTERFACE
(565-256)
POWER SUPPLY
(636-341)
P3
TB1
TO PROGRAMMER CABLE
CITY, TBL, RUI COMM
TB1
TB2
TB3
TB4
I/O #1
I/O #2
I/O #3
I/O #4
P6
P9
TB5
P8
P5
MAPNET
+36V, 0V
+5V, +28V, 0V
P2
BATTERY HARNESS
AC POWER
STATUS / CONTROL
STATUS & CONTROL / +28 UPS
COMM / POWER (+28, +5, 0V)
P2
P4
P3 +36V TO OPTION BOARD
J1
P7 COMM / POWER TO OPTIONS
+28V / 0V / CHARGER
(RED / BLK / YEL)
TB1
OPTION INTERFACE
P9
TB1
H1 – H3
P1
TB2
A TAP
TB3
B TAP
TB4
C TAP +PMSI LOOP PLUG
Figure 2-1. 4020 System Block Diagram
(Universal Supply Installation)
4020 Master Controller,
Continued
System Block Diagram
(Universal Supply)

2-5
KEYPAD/LEDs
LCD DISPLAY
MASTER CONTROLLER
(565-325)
P1
P8
P2
STANDARD SLAVE
(565-222)
POWER I/O INTERFACE
(565-220)
POWER SUPPLY
(636-289)
P3
TB1
TO PROGRAMMER CABLE
CITY, TBL, RUI COMM
TB1
TB2
TB3
TB4
I/O #1
I/O #2
I/O #3
I/O #4
P6
P9
TB5
P8
P5
MAPNET
+36V, 0V
+5V, +28V, 0V
TB1
J1
BATTERY HARNESS
AC POWER
STATUS / CONTROL
SUPPLY CONTROL & MONITOR
COMM / POWER (+28, +5, 0V)
P8
P2
P9 +36V TO OPTION BOARD
P1
P7 COMM / POWER TO OPTIONS
J3
AC MONITOR / +24 UPS
A & B TAPS
J1 J2
P5
P5
P7
P7
A TAP
B TAP
Figure 2-2. 4020 System Block Diagram
(Intelligent Supply Installation)
4020 Master Controller,
Continued
System Block Diagram
(Intelligent Supply)

2-6
Figure 2-3. 565-325 Master Controller PCB Assembly
Table 2-2 describes the I/O connectors on the Master Controller PCB Assembly
(refer to Figure 2-2 for the location of these connectors).
Table 2-2. 565-325 Master Controller PCB Assembly I/O Connectors
Label Description
TB1 External Comm, City Circuit, Trouble Circuit
SW1 Reset Switch
JW1 – JW2 Selects U18 size
•JW1-OUT, JW2-OUT: 2 Meg
•JW1-OUT, JW2-IN: 4 Meg
P1 Keypad connector
P2 Power / Comm Connector to Slave
P3 CFIG Download Programmer Port
P4 City Circuit Jumpers
P5 CFIG Flash Programming Jumper
•Enable Flash Programming – 1-2
•Disable Flash Programming – 2-3
P6 Carrier Detect TXD Enable (1-2 Normal, 2-3 Modem)
P7 RAM Battery Jumper (normally 1-2)
Continued on next page
4020 Master Controller,
Continued
Master Controller PCB Layout
Master Controller PCB
Assembly I/O Connectors
P1
P6
P4
TB1
P3
P5
JW2
P7
JW1
P2
SW1
U8 CFIG
(Note Orientation)

2-7
The Standard Slave PCB assembly controls and supervises four I/O circuits, a
single Mapnet channel and the Power I/O Interface assembly and has the
following features:
•A bi-directional 8 bit bus permits supervision and control of the Power
Supply via the Power I/O Interface assembly.
•The Standard Slave communicates with the Master Controller via Serial
communications. This is accomplished through optically isolated transmit
and receive.
•Mapnet + 5V, +28V and +36V DC power is imported from the Power I/O
Interface assembly.
•The Standard Slave I/O circuits are configurable with wire color-coded
jumper plugs described in Table 2-3.
Table 2-3. Jumper Plug Color Code Scheme
Color Circuit Function Part Number
Red Monitor 733-712
Blue Signal 733-713
White Security 733-806
No plug Auxiliary Relay –––––––
Kit of 6 red, 6 blue, and 3 white jumpers: Part No. 740-769
The Standard Slave:
•Includes interface for Master Controller communications
•Controls the single Mapnet channel & provides 4 hard-wired I/O points
•Controls the Power Supply via a parallel bus Power I/O Interface
•Includes switch SW1 for Slave Card address & SW2 for battery selection
•Receives +5V, +28V & 36V DC power from Power I/O Interface
•+28V I/O Circuit & +36V Mapnet power control
Two different Standard Slave assemblies exist for specific usage:
1. 565-368 Standard Slave with U11 741-033 software is required for use
with: •636-341 Universal Switcher Power Supply (Gold Wing)
•565-256 Power I/O Interface PCB
2. 565-222 Standard Slave with U11 software (Part No. 741-008) is required
for use with:
•636-289 Power Supply (Black Hawk) or 636-370 w/charger adapter
•565-220 Power I/O Interface PCB
Note: 4020 is not approved by UL for 110AH batteries because of
charger overheating and elevated temperatures within the
cabinet.
Continued on next page
4020 Standard Slave
Description
Standard Slave Functions
Application

2-8
Figure 2-4. 565-222 & 565-368 Standard Slave PCB Assembly
Table 2-4 describes the I/O connectors on the Standard Slave PCB Assembly
(refer to Figure 2-4 for the location of these connectors).
Table 2-4. 565-222 and 565-368 Standard Slave I/O Connectors
Label Description
TB1 – TB4 I/O Connections for NAC’s, IAC’s & Control Contacts
TB5 Mapnet Interface Connector
JW1 – JW2 Selects U11 size
•JW1-IN, JW2-OUT: 32K
•JW1-OUT, JW2-IN: 64K
SW1 Communication
•1–7
ON; 8 OFF (Address 01, Baud rate 9600 )
SW2 Batteries selection
•Standard: 1–3
ON, 4 OFF for lead acid battery
P1 – P4 I/O Configuration Plugs
P5 5V and 28V Power Input From Power I/O Interface
P6 & P7 System Comm, Coded Bus and 5V& 28V To Master &
Peripheral Cards
P8 36V Mapnet Power Connector
P9 Interface Connector for Power I/O Interface Card
Communications
4020 Standard Slave,
Continued
Standard Slave PCB Layout
Standard Slave PCB
Assembly I/O Connectors
P8
JW1 JW2
SW1
SW2
P9
P5
P6
P7
P1
TB1
TB2
TB3
TB4
P2
P3
P4
TB5
U11

2-9
The Power I/O Interface circuitry permits the Standard Slave to supervise and
control the Power Supply. A bi-directional 8 bit bus provides Standard Slave
access to Power I/O Interface status and control registers.
The Power I/O Interface assembly converts +28.5 volt A-tap power to 36V
Mapnet power.
Local 28 UPS unswitched power, battery relay control and primary power
supervision is provided by the P9 ribbon cable connection to the Power Supply.
Note: The 28 UPS power is essential for generation of the +5V system
power required for all sub-assembly operation and power supply
supervision and initialization.
The Power I/O Interface assembly provides tap voltage control. Jumper plugs
enable current-limiting Tap Voltages.
Ground fault detection is also performed on this assembly.
The Power I/O Interface:
•Is the interface for power supply supervision & control
•Converts 28.5V DC power to +5V & +36V
•Includes A/D converter for power supply voltage & current supervision
•Monitors Power Supply trouble indications
Two different Power I/O Interfaces exist for specific usage:
1. The 565-256 Power I/O Interface is used with:
•636-341 Universal Switcher Power Supply (Gold Wing)
•565-368 Standard Slave PCB
•Software EPROM 741-033 plugged into U11 on Standard Slave
2. The 565-220 Power I/O Interface is used with:
•636-289 Power Supply (Black Hawk) or 636-370 w/charger adapter
•565-222 Standard Slave PCB
•Software EPROM 741-008 plugged into U11 on Standard Slave
Continued on next page
4020 Power I/O Interface
Description
Power I/O Interface Functions
Application

2-10
Figure 2-5. 565-256 Power I/O Interface PCB Assembly
Figure 2-6. 565-220 Power I/O Interface PCB Assembly
Figure 2-7. Voltage Points on Power I/O PCB Connectors and Terminal Blocks
Continued on next page
4020 Power I/O Interface,
Continued
Power I/O Interface PCB
Layout
P4
J1
P5
P12
TB2
TB3
P10
P13
TB4
P14
P11
P9
P8
P7
P1
P2
P3
P6
RED
BLK
YEL
R139
P1
P2
J1
J2
P3
P4
P5
P6
P7
TB1
P8
P9
+ 24 V A-tap ( TB2 )
+ 24 V B-tap ( TB3 )
+ 24 V C-tap ( TB4 )
565-256 TB2, TB3 or TB4 Terminal Block565-256 P2 or P3 Connector
565-220 P8 or P9 Connector 565-220 TB1 Terminal Block
565-256 P4 Connector
0 V
+ 24 V (System)
+ 5 V (Std Slaves)
0 V
3 6
2 5
1 4
565-220 P2 Connector
0 V
+ 24 V (System)
+ 5 V (Std Slaves)
0 V
4 1
5 2
6 3
Trouble
(Low = Trouble)
+ 36 V
(Mapnet)
0 V
4 3
2 1
Trouble
(Low = Trouble)
+ 36 V
(Mapnet)
0 V
1 2
3 4
B– Return
B+ Return
0 V B
+24 V B-tap
A– Return
A+ Return
0 V A
+24 V A-tap
8
7
6
5
4
3
2
1
0 V
6 5 4 3 2 1
+ Return
– Return

2-11
Table 2-5 describes the I/O connectors on the 565-256 Power I/O Interface PCB
Assembly (refer to Figure 2-5 for the location of these connectors).
Table 2-5. 565-256 Power I/O Interface PCB Assembly I/O
Connectors
Label Description
P1 Power Module Supervision Interface (PMSI) Interface
P2 & P3 Mapnet Power and 36V Converter Trouble Signal Output
P4 5V & 28V System Power Output To Standard Slave Card
P5 Battery Supervision Jumper (1-2 battery, 2-3 no battery)
P6 Trickle Adjust - NICAD
P7 Connection For Current Limit Resistor 1
P8 Connection For Current Limit Resistor 2
P9 Interface To Power Supply (PS Status & Control / 28UPS)
P10 B-tap Enable
P11 Unswitched Tap Enable
P12 A-tap Enable
P13 NiCad Trickle Adjust
P14 C-tap Enable
J1 Standard Slave Interface Connector
TB1 Option Interface
TB2 A-tap Output Connections
TB3 B-tap Output Connections
TB4 C-tap Output Connections
R139 Battery Load resistor
Power Cable Connections: Red +28V / Black 0V / Yellow Charger
Table 2-6 describes the I/O connectors on the 565-220 Power I/O Interface PCB
Assembly (refer to Figure 2-6 for the location of these connectors).
Table 2-6. 565-220 Power I/O Interface PCB Assembly I/O
Connectors
Label Description
P1 Standard Slave Interface Cable
P2 5V & 28V System Power Output To Standard Slave Card
P3 Unswitched tap Enable
P4 A-tap Enable
P5 A-tap In
P6 B-tap Enable
P7 B-tap In
P8 & P9 Mapnet Power and 36V Converter Trouble Signal Output
TB1 A & B Tap Connections
J1 Supply Control & Monitor Connections To Power Supply
J2 Supply AC Monitor / 24UPS Connections To Power Supply
4020 Power I/O Interface,
Continued
Power I/O Interface PCB
Assembly I/O Connectors

2-12
The Switcher Power Supply converts 120/220/240VAC input line voltage into
28 volt DC power. The supply provides brownout detection status to the Power
I/O Interface board.
A relay permits the Standard Slave to select power from either the Power Supply
or battery. An over voltage protection circuit supervises the DC output to
prevent system sub-assembly damage.
The Power Supply:
•Converts 120 or 240 VAC to 28 VDC
•Provides battery changeover circuitry (controlled by Slave)
•Monitors batteries under the control of the Standard Slave
•Detects brownout or AC power loss and reports it to the Standard Slave
Note: Brownout is NOT Field adjustable.
Two basic Power Supply assemblies exist for specific usage
1. 636-341 Universal Switcher Power Supply (Gold Wing)
•565-368 Standard Slave PCB with U11 741-033 software
•565-256 Power I/O Interface PCB assembly
2. 636-289 Power Supply (Black Hawk) or 636-370 w/charger adapter
•565-222 Standard Slave PCB with U11 741-008 software
•565-220 Power I/O Interface
Caution: DO NOT OPEN switcher. The switcher is not field serviceable
and contains lethal, high voltage.
Table 2-7 describes the I/O connectors on the 636-341 Power Supply (Gold
Wing Supply).
Table 2-7. 636-341 (Gold Wing) Power Supply I/O Connectors
Label Description
P1 AC Input and Voltage Select Jumper
P2 Power I/O Interface Interconnections (status &control 28UPS)
TB1 28.5VDC Output To Power I/O Interface Board
Battery Harness: Battery Charger Output & Battery Power Input
Table 2-8 describes the I/O connectors on the 636-289 Power Supply (Black
Hawk Supply).
Table 2-8. 636-289 (Black Hawk) Power Supply I/O Connectors
Label Description
J1 Control & Supervision Signals
J3 +24UPS / AC Power Status
P1 Battery Harness
P4 B-tap Voltage To Power I/O Board
P5 A-tap Voltage To Power I/O Board
4020 Power Supply
Description
Power Supply Functions
Application
Power Supply I/O Connectors

3-1
This chapter presents 4020 problems experienced in the field and those analyzed
by Service Repair. This information is arranged in three categories:
•General Issues
•Problems Associated with Assembly / Dis-Assembly and Installation
•Problems Associated with Power Supplies
Service Repair data indicates that system problems are most likely to reside in
the Standard Slave PCB assembly followed by the Power I/O Interface card.
Based upon Service Repair records, the estimated distribution of 4020 system
PCB failures is: 41% Standard Slave
33% Power I/O Interface
15% Master Controller
11% Universal Switcher Power Supply
Most Standard Slave problems appear to occur during the system installation
phase or during upgrades. Many system problems appear to result from
improper system wiring during installation or system upgrade.
Because of the individual sub-assembly interaction, what may appear to be a
power supply problem may, in fact, be caused by a problem on either the
Standard Slave or Power I/O Interface assembly.
A great deal of system complexity has been concentrated on the Standard Slave
Assembly and a considerable amount of interaction between assemblies is
required for proper system initialization and operation. Again, because of sub-
assembly interaction, what may appear to be a power supply problem may, in
fact, be caused by a problem on either the Standard Slave or Power I/O Interface
assembly.
Chapter 3
4020 Problem Experience
Overview
Where Problems are likely to
Reside
Troubleshooting Difficulty

3-2
Removing the AC power cable connection from the Power Supply still leaves
primary AC power on the terminal block to the right of the supply. During
supply removal it is possible to contact the primary AC power which is observed
on many power supplies and is evidenced by arcing marks on the top surface of
the heat sink.
Upgrades should not be performed with system power on. This practice
damages Mapnet and NAC circuits by backfeeding AC power into circuits
powered from the A & B taps. This over-voltage condition accounts for
significant Power I/O Interface and Standard Slave Mapnet & I/O circuit
damage.
Over-voltage in excess of 35 to 40 volts destroys the Power I/O Interface MOV
transient suppressers between the A & B taps and 24C ground and/or between
the 24C ground and earth.
Contractors should understand how to properly wire peripheral devices handling
AC power.
The fuse wiring harness (Part No. 733-731) referred to in the 4020 Field Wiring
Diagram (841-842, sheet 22) is available to limit B-tap over-voltage damage..
Most Master Controller PCB assembly failures appear to be the result of
electrostatic discharge (ESD) into the Master Controller. ESD may be entering
the system during the installation of the U8 flash device or from contacting the
installed flash chip during connection of the download cable onto the adjacent
P3 header connector.
Note: Static electricity can damage components. Use the following
precautions:
•Ground yourself before opening or installing components
(use the 553-484 Static Control Kit).
•Keep uninstalled components wrapped in anti-static material
at all times.
System ground faults are normally due to field wiring problems, but it is
possible for ground faults to occur within the power supply. Excess leakage
current on capacitors C36 and C38 of the Power Supply Universal Switcher
PCB assembly (Part No.565-235) has been known to cause system ground
faults.
On at least one occasion it was reported that the drop panel retention wire
insulation was fractured and the wire shorted to one of the PCB assemblies. In
this instance, the ground fault disappeared whenever the front panel was opened.
Continued on next page
General Issues
Damage Caused by Live AC
Power
Damage Caused by
Upgrading Live Circuits
Damage Caused by
Electrostatic Discharge (ESD)
Ground Faults

3-3
Two Standard Slave PCB assembly versions exist. Although the assemblies
appear to be identical, each assembly requires specific Software, Power I/O
Interface assembly and Power Supply for proper operation.
Older 4020 systems WITH: 636-289 4020 Intelligent Power Supply (Black Hawk) OR
636-370 w/charger adapter
REQUIRE: 565-222 Standard Slave assembly with U11 software (741-008)
AND: 565-220 Power I/O Interface assembly
Newer 4020 systems WITH: 636-341 Universal Switcher Power Supply (Gold Wing)
REQUIRE: 565-368 Standard Slave assembly with U11 software (741-033)
AND: 565-256 Power I/O Interface assembly
Some Standard Slave assemblies in the field may have an assembly software
version installed without the appropriate PCB assembly designation being
marked.
When a technician services the site, the incorrect assembly part number on the
board may mislead the technician into ordering the wrong Standard Slave
replacement assembly with incompatible software. The incorrect Standard Slave
assembly then complicates system troubleshooting and repair.
Although the wrong Standard Slave Assembly should not cause damage, the
system will not initialize properly because of the software incompatibility.
Field service personnel have reported that lightning accounts for significant
panel damage in certain geographical areas.
Proper lightning suppression equipment is essential for all outside field wiring
entering the building. It is recommended that these devices be located as close as
possible to the building entry point. In certain areas, transient protection is
recommended for both outside field wiring and incoming AC power to the
panel.
For detailed information concerning how to protect Simplex systems refer to the
Transient Suppression Methods for Simplex Equipment document (Pub No.
GEN-11-006).
General Issues,
Continued
Initialization problems due to
Improper matching of PCB
Versions
Lightning Damage