A-2
Chadwick-Helmuth A Business Unit of Honeywell International, Inc.
Appendix A -
8520C-36 Signal Selector
•
Pulse Detector
•
Microcontroller
•
Velocimeter Built-in Test (BIT)
The 8520C-36 controller board also contains four pulse detectors, which have the same function as the
8520C quad peak detector board A3.
A.3.4
Power Supply Board A2
The power supply board A2 is identical in function to the power supply board in the 8500C/C+ (see
Section 4.2.1.2.3, “Power Supply Board”).
Figure A-1. 8520C-36 Controller Board and Mux Board Block Diagram
A.4 Maintenance
A.4.1
Introduction
To test the 8500C/C+/8520C-36 system with a nacelle harness assembly, you will use a test that was
adapted from the function test in Chapter 5, “Maintenance.” Certain procedures in this Chapter will
reference those found in Chapter 5 as well.
A.4.2
Test Equipment
For the most part, you will be using test equipment listed in Table 5-1. In addition, you must fabricate
a test cable to perform tests that do not use the nacelle harness. For fabrication instructions, see Section
A.4.6, “Testing 8520C-36 without Nacelle Harness Assembly.”
PICKUP INPUT 1
PICKUP INPUT 2
PICKUP INPUT 3
PICKUP INPUT 4
4:1 MULTIPLEXER
4:1 MULTIPLEXER
PICKUP SIGNAL
TO 8500
DIGITAL BOARD
2 CHANNELS
2 CHANNELS
A-B FUNCTION BLOCK
A+B FUNCTION BLOCK
A+B FUNCTION BLOCK
A-B FUNCTION BLOCK
2:1 MULTIPLEXER
2:1 MULTIPLEXER
PEAK DETECT AND HOLD
ANALOG-TO-DIGITAL
CONVERTER
SERIAL
COMMUNCIATIONS
TO/FROM 8500
DIGITAL BOARD
63A03A
MICROCONTROLLER
+ 12 VDC
LATCH
POWER SWITCH
POWER
MONITOR
SHORT
CIRCUIT
LAMP
VELOCIMETER BIT
PULSE DETECTOR
FILE: SS36BLK.DRW
36:4
CROSSPOINT
SWITCH
TO 8500
ANALOG BOARD
VELOCIMETER INPUT 1
VELOCIMETER INPUT 2
VELOCIMETER INPUT 3
VELOCIMETER INPUT 4
VELOCIMETER INPUTS 5 THRU 12
VELOCIMETER INPUTS 13 THRU 20
VELOCIMETER INPUTS 21 THRU 28
VELOCIMETER INPUTS 29 THRU 36
BROADBAND
PULSE DETECTOR
PULSE DETECTOR
PULSE DETECTOR
CONTROLLER BOARD
MUX BOARD
