Open source comms/power schematic diagram software

Question

I am designing a communication/monitoring system for a remote site as a personal project, and I would like some way of documenting the following attributes for the site, so I can refer back to them later without having to make the four-hour round trip there and back:

• How the power is routed from solar panels, through charge controllers, to batteries and to powered devices - including cable thicknesses, maximum amp ratings, fuse/breaker ratings, etc.
• How the data network is wired - what switch ports connect to which devices, whether PoE is used, what VLAN and subnets are used, etc. (including WiFi links)
• How RS485/Modbus links are wired, device addresses, baud rates, etc.

It would be ideal if these could be layers in the same application, so I could for example switch off the network layer to just look at the DC power layer.

Are there any open source applications like this?

• Mind mapping software may work but it seems less than ideal as it's more about how ideas connect together than matching the state of a physical layout.
• CAD software would also work but it seems much lower level, dealing with lines and labels rather than a conceptual "link" between devices.
• Network mapping software may work (such as the suggestions in this question), but it doesn't look like they support layers for things like DC power connections of various voltages and amperages. They seem to focus on identifying devices and links automatically, but I am still at the design stage, having not assembled anything yet, so no automation would help me there.
• Diagramming software like Microsoft Visio might work, but I don't know of any good open source alternatives that can cater for my use case. LibreOffice Draw and Pencil seem to be the top recommendations but they don't seem to do things like update all the links (lines) between devices as you move them around.

I'm running under Linux so open source software would be preferred.

Answer 1

I ended up using KiCAD for this. It is meant for designing electronic circuits, but it also works well for joining symbols together with one or more "wires". It does an ok job of moving the wires around as you move blocks around, but it still requires a lot of manual effort - you just don't have to be pixel perfect like with some other diagramming tools.

It allows me to design custom circuit symbols with a specific number of input and output pins, which I can use to describe the various connectors. Each symbol can have additional text fields which can be used for information such as Modbus address, baud rate, IP address, VLAN, DC voltage, etc.

It's definitely a bit hacky shoehorning this purpose into KiCAD, but it's usable, and it produces schematic diagrams that are easy enough to follow for my purposes.

Here is a partial screenshot of what I have produced with KiCAD: