Mains/battery changeover

We had a power cut this morning. When I switched the changeover switch to battery power I could hear a relay trying to switch in the inverter but the battery wouldn't stay connected. It's always worked when needed in the past (it's a rural area with frequent power cuts), but I can't remember if I've needed to changeover to battery since we went onto Intelligent Octopus Flux. Does this tariff disable manual switching to battery power? The battery was full, having charged overnight.

Roblev Octopus take full control of your battery charging and discharging but you would think you would still be able to access the emergency power capabilities of the battery despite being on IOF, but I don’t know, never heard this question before.

Might be worth asking Octopus for confirmation that you can still change over the battery to supply the house in the event of a power cut.

OIF might not be the best tariff to be on for the winter. Its principle advantage (aside from being fire and forget) is the decent export rate, but in the winter with little solar, this isn’t really happening.

You might get better results being on Economy 7 or Flux for the winter, charging overnight and using the battery during the day/night

geoffreycoan Thanks Geoffrey, I'd decided I'd contact Octopus if nobody came up with an obvious solution here. I was pretty sure IOF should allow me to use the battery but this made me wonder.

Maybe when I flipped the changeover switch there was too much current demand, say from the Eddi water heater on top of the base load, for the inverter to manage. I'll play with turning Eddi off before changing over and see if that helps. Otherwise it's a case of waiting for the next swan to fly into the power lines!

Yes, I'd wondered about whether IOF was the best in winter, but after it took me months of wrangling with Octopus to get on the tariff, along with sorting out repairs to a faulty smart meter, I'd had enough of complications. As a result I find it hard to believe that switching tariffs can be straightforward. At least I made a helpful contact in Customer Services after several irrelevant stock responses from poorly trained staff and, even worse, nonsensical AI "help". So I will consider your suggestions.