A custom switchboard is one of the few items on a job that you can't swap out easily if it turns up wrong. It sits on the critical path, it carries the fault current, and the name on the compliance paperwork is the one everyone looks at if something goes badly. So picking a manufacturer on price alone is a risk. Here is what electricians, contractors and wholesalers should actually check.
1. Can they show design verification to AS/NZS IEC 61439?
AS/NZS IEC 61439 is the standard for low-voltage switchgear and controlgear assemblies. It puts the responsibility on the assembly manufacturer to verify the design: temperature rise, short-circuit withstand, clearances and creepage, dielectric properties, protection against electric shock and more. Ask a direct question: how was this design verified, and can I see the evidence? A good manufacturer will answer without fuss and supply the documentation with the board. A vague "it's built to the standard" is not the same thing.
If you want the background, we covered it in our article on what AS/NZS IEC 61439 means and why form separation matters.
2. Do they ask the right questions up front?
You can tell a lot from the first conversation. A manufacturer who knows their work will want the prospective fault level at the point of supply, the main switch rating, the form of separation, the IP rating and location, cable entry (top or bottom), metering arrangements and the space available on site. If nobody asks about fault level or where the board is going to live, expect variations later.
3. Do they know your network's requirements?
Every distributor publishes its own rules for service and metering equipment, and they differ in the details. A board that suits one network area can need rework in another. If your job is in the Endeavour Energy area, which covers Western Sydney, the Blue Mountains, the Southern Highlands, the Illawarra and the South Coast, use a manufacturer who builds for that network regularly and checks the current requirements before drawings are issued, not after the board is on the truck.
4. Are the lead times honest?
Most delays on a custom build come from two places: late drawing approval and long-lead components such as large circuit breakers. A realistic manufacturer will tell you which parts set the schedule, what they need from you to keep things moving, and when the clock actually starts. Be wary of a short lead time quoted before anyone has seen the single line diagram.
5. What do you get with the board?
The enclosure is only part of the delivery. Check that the price includes approval drawings, as-built drawings, a circuit schedule, clear labelling, routine test records and the design verification documentation. These are the things your certifier, the client's facilities team and the next electrician on site will all ask for.
6. Can they handle what's coming next?
More and more boards now need to allow for solar, battery storage, EV charging and generator changeover, either on day one or as a future provision. A manufacturer who also works with energy systems will leave sensible space, busbar capacity and metering provisions for it. That is a large part of what we do: alongside switchboards, WISE designs battery and off-grid power systems for industry right across Australia.
7. Can you get a person on the phone?
Things change on site. Cable sizes grow, a tenant adds load, the builder moves a wall. You want a manufacturer where the person who drew your board will pick up the phone, and where a modification can be turned around without starting again. Local and accessible beats cheap and distant when the job is under pressure.
A quick checklist
- Design verification evidence to AS/NZS IEC 61439
- Fault level, form, IP rating and site constraints confirmed before quoting
- Experience with your distributor's service and metering rules
- A lead time tied to drawing approval and component availability
- Drawings, schedules, labels and test records included
- Provision for solar, battery and EV charging
- Direct access to the people building it
WISE Energy builds large custom switchboards at our Unanderra workshop for electricians and wholesalers, design-verified to AS/NZS IEC 61439. See switchboard manufacturing for what we build, or read why contractors choose WISE. Send us your single line diagram, or call 1300 368 331 to talk a job through.