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What do I need to know about technical diagrams for inverter energy systems?

Single line diagram

A single line diagram needs to contain information on the installation wiring from the point of supply off the Western Power network, through to all the inverters on site, including where the customer’s load is connected. 

It also needs to contain information on all protection devices and switches, as well as any communications required to achieve the desired operation of the system (i.e. self-consumption, export limit, etc.).

All diagrams should contain at least, but not limited to, the following information specific to the site in question:

  • point of supply off the Western Power network
  • Western Power meter
  • any private smart meters where used
  • distribution boards
  • load
  • all inverters – new and existing
  • energy source (PV array, batteries, etc.)
  • communications and controls (where used)
  • protective devices
  • cable size and length between all the above

Cabling diagram

A cabling diagram (or screen shot) of the site shows the location of the cable path between each of the following:

  • supply type (overhead or underground)
  • pillar (if underground) or point of attachment (if overhead) or pole top transformer (if sole use)
  • Western Power meter
  • main switchboard
  • sub boards (if any)
  • inverter/s – new and existing

This information allows our assessor to confirm the site and determine the voltage rise for your proposed system. If we don't receive this information, we won't be able to process the application.

Examples of cable diagrams





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