Published: Thursday, 22 January 2026 • Area: Morangup / Greater Eastern Hills (WA)
If your power drops out briefly on a very hot afternoon and then comes back by itself about half a minute later, you’re most likely seeing a network protection device doing its job — not “random faults” inside your house. Morangup Residents Group — Community explainer
What residents are noticing
On extreme heat days (often still close to 40°C near late afternoon), some parts of Morangup can experience short, repeat interruptions — commonly around 20–40 seconds — while other roads remain unaffected. The pattern many people report is that it happens right when households arrive home and switch on high-load appliances: air-conditioning, ovens, cooktops, hot-water boosts, pumps, workshops, etc.
The simple explanation
Morangup is supplied via a rural distribution network with multiple branches. During the hottest part of the day, the network is already under stress from heat. Then, when many homes switch on cooling and cooking at the same time, the supply can hit a practical limit on a particular branch of the feeder.
The network protection system reacts by opening (turning off) that section briefly, then automatically restoring it — which is why it can look like a “trip” that self-resets.
Why it happens right when people switch things on
Air-conditioners are the big one. Many modern systems draw a large current when they first start. This is called start-up / inrush current. If a lot of systems start within the same few minutes on the same local supply branch, the surge can briefly look like a fault condition to upstream protection devices.
- Heat raises demand: everyone’s cooling at once.
- Inrush spikes: compressors starting together can create short, sharp surges.
- Long rural lines: longer distances can mean more voltage drop when loads jump.
- Protection does its job: it opens quickly, then tries again after a short “dead time”.
Why it’s often about 30 seconds
Those upstream devices (often called auto-reclosers) are designed for overhead rural networks. Their job is to open the circuit when a problem is detected, pause for a preset interval (the “dead time”), then reclose automatically if the fault was only temporary.
A ~30 second gap is a very common “slow reclose” setting that gives time for the surge to pass, motors to settle, and the network to stabilise.
Why some roads drop and others don’t
This is the key point: Morangup’s network is not one single pipe. It’s a tree of feeders and branches. Neighbours can be on different branches, different transformers, or even different phases.
- Different branch / lateral: one section hits a limit and trips, another doesn’t.
- Different transformer group: load density varies by pocket and street.
- Distance matters: the further from the “backbone”, the more sensitive you can be to load surges.
- Local solar/batteries help: homes running from batteries may not feel the dip at all.
Pros and cons of the “auto-reclose” behaviour
Pros
- Fast restoration: brief interruptions are restored automatically without a crew.
- Protects equipment: helps prevent damage to lines and transformers under stress.
- Reduces escalation: a short trip can prevent a bigger, longer outage.
Cons
- It’s disruptive: lights, internet, routers, and appliances can reset.
- It can repeat: multiple trips may occur if peak demand keeps surging.
- Not everyone is affected equally: different branches = different experiences.
What to expect on very hot days
If the pattern is peak-load related, the risk window is commonly late afternoon into early evening (roughly when households return home and cooling/cooking ramps up). It may ease later at night once outdoor temperatures drop and demand spreads out.
Quick “what can I do right now?” checklist
- Stagger start-ups: if you have multiple air-cons, avoid starting them at the exact same time.
- Pre-cool earlier: start cooling before peak time (mid-afternoon) so compressors don’t all slam on at once.
- Ease the set-point: 24–26°C can reduce compressor cycling and peak draw.
- Avoid stacking loads: don’t start oven + dryer + workshop + hot-water boost all together at 5pm.
- Protect electronics: consider a small UPS for modem/router so internet stays up during the 30s dip.
Community-level ways to minimise the impact
No one household “causes” it. It’s a coincidence issue: lots of homes switching on heavy loads at the same time on a rural feeder. The best community impacts come from smoothing the peaks.
- Spread the ramp-up: if possible, avoid everyone turning on all cooling at the same minute after work.
- Use timers: set AC to start at slightly different times across the household (even a 5–10 minute offset helps).
- Battery/solar where feasible: local storage reduces demand on the line at the exact stress window.
- Report patterns: if you see repeat events, log the time and suburb/road pocket. Patterns are useful.
- Keep it factual online: “some feeder branches appear capacity-limited at peak heat load” beats rumours.
What about “getting 3-phase”?
Before anyone asks: 3-phase is not an easy switch in rural areas. It is not just a paperwork change. It can require network upgrades (poles, conductors, balancing), transformer capacity, and a suitable service run.
Also: 3-phase doesn’t magically reduce total energy use. It mainly spreads large loads more evenly across phases. If the whole branch is near capacity, upgrades are still upgrades. Plain-English note for rural networks
FAQ
Is this an issue inside my house?
If the whole street/pocket goes off then returns about half a minute later, it’s usually upstream network behaviour. If only your house trips, that can be a private wiring issue (main switch, RCD, appliance fault).
Why does it happen more on 40°C days?
Heat drives demand and increases stress on lines and equipment. Peak demand coincides with people arriving home, cooking, and pushing cooling harder.
Why do battery homes say “we’re fine”?
If you’re running from batteries (or exporting solar), your home can ride through a short dip. You’re also drawing less from the local feeder, which helps the broader supply.
Is it “grid overload”?
“Overload” is a loose word people use. The more accurate idea is: peak coincident demand on a specific feeder branch exceeds what that section can comfortably support (current, voltage stability, and protection thresholds).
What should I do if it keeps happening?
- Note the times, how long it lasts, and whether neighbours on your road were affected.
- Consider a small UPS for modem/router if you rely on internet for work/phones.
- If you have multiple high-load appliances, try the “stagger start” and “avoid stacking loads” tips above.
Community note: This article is a plain-English explainer based on common rural distribution behaviour and observed local patterns. For faults, danger, fallen lines, or urgent electrical hazards, always follow official channels and emergency advice.