Wire Numbering Standard

MHennel said:

This subject can get real ugly. Personally I agree that wires of the same potentail should be labeled the same, but I am old school and in the US. I have also gone between sheet/line number, to using I/O point address..

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We typically use I/O address because we are PLC centric - Typically we need to be able to find the device in the program more often than the drawing set.

Rson said:

We typically use I/O address because we are PLC centric - Typically we need to be able to find the device in the program more often than the drawing set.

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That makes it easier to troubleshoot... wire number correlates directly to logic.
No prints needed... yet

NetNathan said:

That makes it easier to troubleshoot... wire number correlates directly to logic.
No prints needed... yet

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Exactly. There is also always an HMI screen that lists all of the I/O with indicators so you can see whether the device is changing state at the PLC level. It is a lot easier than trying to write the wire number on each device.

One of our customers states it this way. Every wire come from one device to another device. So they enforce from/to tags. For example a tag that reads PS01+/PLC01PSVCC (using 2 line wrap around self laminating markers) is the positive from the power supply to the positive on the PLC power supply.
Panel shop guys hate it. But trouble shooting people love it. On big jobs where there is more than one panel you have to add panel number to that. Like 1PS01+/1PLC01PSVCC
One of the engineers there asked once if we could add the terminal block and terminal to it also. The boss flat out said no, and they never asked again.
Could you imagine a tag of 1TB1T2-PS01+/1PLC01PSVCC

JaxGTO said:

…….One of the engineers there asked once if we could add the terminal block and terminal to it also. The boss flat out said no, and they never asked again.
Could you imagine a tag of 1TB1T2-PS01+/1PLC01PSVCC

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As a system integrator, we did work for a big pharma company and their tags were like this. Some were 25 or more characters long. Too many entry errors when printing tags.

They like it this way because due to their idiotic rules they would not permit prints to be kept in a panel. Reasoning being that the only certified prints were stored on the server. As soon as they were printed out they became obsolete. Stupid, stupid, stupid.