Schematics for the equipment I design and build almost always span multiple pages, even if the gear is only a single cabinet (we like to densely populate our cabinets).
To make it easier to build and troubleshoot, and to keep track of the page the part you're working on is from, I number schematic pages and wires like this:
EXAMPLE:
Schematics are plates 1.0 through 1.16
Wires that originate (and usually are only part of) plate 1.0 start at 0.0 and go up to 0.xxx
Wires that originate (and usually are only part of) plate 1.12 start at 12.0 and go up to 12.xxx
Occasionally, I'll end up with a set of wires in parallel (I do lots of theatrical LED lighting, and many dimmers double up on the common-positive output terminals for voltage drop reduction). In the case of parallel wires on plate 1.5, they'd be labeled 5.4A and 5.4B
The same wire number goes on both ends of the wire on a Brady wire label. All devices get a P-touch label on them, or the backplane is P-touch labeled if that's easier/necessary.
Often, you'll end up with wire numbers from one page spanning to others especially things like 24VDC and 120VAC control voltage - but you always know what page they originated from.
I too am of the belief that a wire does not change number unless it goes through a device, even if that wire branches out through a set of terminal blocks; 24VDC power is a perfect example of this.
Our shop guys seem to like this method, and it's a damn sight easier to troubleshoot when you've got your head buried up to your shoulders in a cabinet inside a piece of Broadway scenery that's full to bursting with equipment.
-rpoet