Owners Left In The Dark With Manual Battery Backup

Imagine buying a home battery that offers automatic blackout protection, only to discover that when the lights go out, the installer set it up to require manual operation? It’s a trend that’s plunged far too many households into the dark across Australia. Here’s what to watch out for.

Is Your Home Battery Set Up To Provide Automatic Blackout Protection?

Why on earth would an installer set up a hybrid solar battery system, one that offers automatic blackout protection, then set it up with a switch that requires manual operation in the event of an outage?

I suspect the answer is they’re trying to avoid a few awkward conversations, namely:

• selecting a limited number of circuits for blackout protection
• extra cost to isolate or re-run the wiring for the fridge
• expensive switchboard rebuilds

That’s not the only way installers are leaving customers in the dark – why are battery owners posting on socials, or contacting SolarQuotes looking for clarity on how their system should actually work?

The company selling the system or the electrician installing it should be the ones explaining and demonstrating exactly how the system they’ve set up should work.

Unless there’s a technical reason, battery backup should happen automatically, without you having to intervene.

This highlighted two way switch controls backup for just two circuits. Though this switchboard has carefully printed stickers it lacks the engraved plastic labels, with specific wording used under today’s standards.

Shonks Will Be Shonks

There are solar retailers out there who’d rather you don’t have blackout protection. Seriously.

They’ve found problems arise when adding complexity to solar power systems. And paying peanuts to the worst subcontractors means things won’t work, the phone will ring and irate customers won’t want to pay.

I guess the cheap equipment they push either needs extra hardware to work (i.e., a long, expensive cable run or a backup box that has to be supplied and wired up correctly) or it’s unlikely to have sufficient surge capacity to cope with backup in any case.

As SolarQuotes founder Finn Peacock noted recently in his piece on battery backup myths, any retailer that recommends point-blank not getting protection is best avoided.

Bypass Switches Are Essential

Many solar battery inverters are what we call series-connected machines – that is, the backup circuits are wired through the inverter.

So whether it’s the whole house or just the modest but essential fridge, lights and internet, the inverter must carry the whole load. And if the inverter fails, so does whatever you have connected through the inverter.

So it’s absolutely essential that when you have a series-connected system, there must be a switch to bypass a broken inverter and reconnect mains power to your essential circuits. The ability to restore power yourself at the flick of a switch is the most basic customer service a solar power company can offer.

Here we have circuit breakers for the input and output of a hybrid inverter, but more importantly the bypass which puts your essential circuits back onto mains power if the inverter fails.

Bypass Switches Can Be Automated

We’ve written specifically about how a modest battery system shouldn’t be routinely overloaded by expecting it to run a whole house. Lightweight hybrid inverters, a run-of-the-mill 5kW inverter, for instance, won’t carry more than about 27 amps, so you can’t feed a 63 amp house load through them, no matter what.¹

Series connected inverters will throttle whatever is connected to the backup port whether mains power is available or not.

Say there’s some extenuating circumstance – the mains connection and solar is on the shed with the house on a downstream distribution board, for instance. In that case your modest inverter can still be connected for “whole home” backup.

Using a contactor to power the house under normal conditions means that if there’s an outage, your backup power will still kick in.

Assuming nobody is home, the freezer will stay frozen, but of course, if the system is overloaded, you’ll still have no power.

Speed Isn’t Everything

Some brands of inverter don’t deliver what you’d call seamless supply. When the grid goes down, they may take up to 15 seconds to re-energise the house, and this is what I’d call a big, unmissable analogue warning for you to pull your head in and reduce consumption.

Some claim response times so fast you’ll never notice a blackout, which can be a bit of a trap if the air conditioning is going to chew through your battery.

Be Aware That Solar Hybrids Are NOT Uninterruptible

Any solar hybrid inverter can drop out and take a minute to restart, especially if the battery is well charged and the sun is shining when the grid fails.

Though fast response times often appear in the marketing material, they are not technically rated for uninterruptible supply, so if you have a mission-critical computer, then an uninterruptible power supply (UPS) will still be needed.

Sungrow are big enough to admit Emergency Power Supply doesn’t meet the stringent rules of a proper uninterruptible power supply – EPS is not UPS.

Perhaps Electricians Are Setting Expectations; Manually

When a system underdelivers, the phone will invariably ring, so perhaps installers are being pre-emptive when they make switchboard connections.

It doesn’t apply so much with the rise of inverters rated for “whole home” backup, but some customers are confused when a 10kW single phase machine is really gutsy compared to a 10kW 3 phase unit which only delivers a third of the capacity per phase.

As the bloke doing the wiring on the day, I’ve had to negotiate with and, in some instances, disappoint customers who thought they’d bought something far more capable. It can be embarrassing for the salesperson who glossed over, or the end user who simply didn’t want to hear, but when a 3kW rated toy won’t cope with much more than the fridge and lights, there’s often some sadness.

Simplifying Things For Installers Not Customers

By fitting the bypass switch as “normally off”, the whole house can be connected to it.

When there’s an outage, you have to go to the switchboard and turn on the backup supply manually, at which point you’re acutely aware of the blackout conditions and the need to reduce your consumption.

So the installing electrician can avoid any conflicts or embarrassment, and indeed just save time by identifying or dividing circuits to cope with a limited inverter capacity.

I’ve had to pull a new cable or chase wiring down walls to separate the fridge from the rest of the house, so I can see the appeal of just whacking in a switch in and telling the customer to “be careful”.

This power point was installed in the ceiling space to connect an internet router but thankfully the cable down the wall to the fridge was also easy to find here.

However, manual backup is fraught with danger because the average punter doesn’t have a good understanding of electrical load. If they don’t appreciate the system, it will struggle to start the rainwater pump, or won’t cope with the kettle and starting the fridge, the lights will flicker, and power might fail.

And of cours,e if you’re on holiday, the freezer is still going to thaw out. Again, this just produces sadness and irate phone calls.

Proper engraved labels for main switches, but still a poor result. A bypass switch could easily go into this enclosure, but the gaping hole they’ve left is illegal.

Knowing The Ground Rules Is Key

These days, anything is possible if you throw enough money at it. I put a 5kW Selectronic SpPro on my place because it’s an exceptional system with 12kW surge capacity that knocks everything else into a cocked hat. Of course, it’s a bit pricey when you want Australian-made, though.

My advice is always make sure you understand what is feasible, or what your budget is going to buy. Make sure the salespeople are aware of your priorities. Obviously, a battery should help reduce your bills and reduce load on the network.

• Do you want to treat the grid with contempt?
• Does the house rely on a pump for rainwater or septic?
• Is backup super important to keep the air conditioning or heating going for a medical reason?
• Is it important to have black start capability to keep things going if there’s an outage that extends for days?
• Or is it just nice to have the fridge, telly and internet for a few hours?

Document what you want and what the system is supposed to deliver, so everyone is on the same page.

Not every battery system needs a bypass switch, but if it does, it should be used only if the inverter breaks down. Like buying a dog and doing your own barking, if you have to switch on your backup supply yourself, you’ve been sold a pup.

Read more about blackout protection for your home on our solar battery explainer page.