Understanding Circuit Diagrams - Fayat Bomag BW 900-50 Service Manual

4.1.2 Understanding circuit diagrams

4.1.2.1 Circuit diagrams
Structure of circuit diagram
Cover sheet
Electric systems – Basic principles
Circuit diagrams provide information on the logical, electrical func-
tions of BOMAG machines and currently do not provide any infor-
mation on how and in which order electrical components are wired
together, even if some directional wiring symbols are occasionally
used.
Wiring information is currently defined exclusively
in the corresponding wiring drawings or wiring
loom drawings.
A circuit diagram is indispensable for effective and systematic
trouble shooting in the vehicle wiring system. This diagram pro-
vides the following information:
n Number and type of individual elements in the examined elec-
tric circuit, such as plug connectors, fuses, switches, con-
sumers, relays, etc.
n The sequence in which current flows through the individual ele-
ments in the electric circuit.
n Connections between the examined electric circuit and other
circuits in the vehicle wiring system.
n Pin assignment of plug-in connections.
The circuit diagram consists of following individual parts:
n Cover sheet (with general information)
on page 69
Ä 'Table of contents' on page 70
n Table of contents
n Overview of structural symbols (only if the structural view is
used) Ä 'Overview of structural symbols' on page 70
Overview of installation locations (only if the structural view is
n
used) Ä 'Overview of installation locations' on page 71
n Electric circuit documents for electrical engineering (functional
Ä 'Functional diagrams' on page 72
diagrams)
n List of components for electrical engineering (without terminals
Ä 'List of components' on page 73
and plugs)
n Overview of terminal strips (form type: terminal diagram)
Ä 'Overview of terminal strips' on page 74
n Overview of pins (form type: PLC diagram)
pins' on page 75
n Overview of plugs (form type: plug diagram)
plugs' on page 75
n Additional graphical information (e.g. CAN structure, overview
of central electrics and control boxes).
The cover sheet contains general information.
BW 900-50
Ä 'Cover sheet'
Ä 'Overview of
Ä 'Overview of
69