I don't have an example handy, but you might try a Google search for
"nailboard drawing." These drawings mimic the manual process of creating
the harness, which involves laying it out full scale on a board with nails
driven to represent runs and termination points. The wires are then strung
along the nails. Nailboard drawings are usually done full-scale.
Nailboard drawings USED to be very often done full scale before large
size plotters went by the wayside for so many companies. Oftentimes now
they are scaled, and sometimes they are multiple sheet to show long
harnesses (some lengths continued from one sheet to another). But at
least one of two other documents (and often both kinds) usually
accompanied nailboard drawings. One was a symbolic wiring diagram and
the other was a wiring list. Wiring diagrams usually show devices as
rectangular blocks and connectors as rows of numbered pins or sockets
with the reference designator of the connector at top, like so:
1>----- - - - 1<------ - - -2>----- - - - 2<------ - - -3>----- - - - 3<------ - - -4>----- - - - 4<------ - - -
Some people will tell you that J reference designators are "Jacks" which
are always symbolized as female and P reference designators are "Plugs"
which are always symbolized as male. About half right. "Jacks" are the
more relatively fixed of mating pairs and should be given a J reference
designation under MOST circumstances and "Plugs" are the more relatively
movable of mating pairs and should be given a P reference designation
under most circumstances . . . but either one can be either gender. The
gender of the symbol should jibe with whether the connector has pins
(male symbol) or sockets (female symbol), and also has nothing at all to
do with how the connector shells are relative to one another (whether
one shell fits inside the mating connector's shell). When two
connectors are both equally movable or fixed the assignment of J or P
reference designation should jibe with the gender of the connections
themselves as above, BUT there are plenty of exceptions there also.
The symbology of wiring diagrams pretty much follows the symbology of
schematic diagrams, which itself is governed by what used to be called
IEEE Std 316 / ANSI Std Y32.2. I don't know what it goes by now.
Assignment of reference designations for wiring harnesses and wiring
diagrams should follow either the Unit Numbering Method or the Block
Numbering Method of IEEE Std 200.
Mark 'Sporky' Stapleton
Watermark Design, LLC
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