Power Booster question

This might be a dumb question but…

As I understand it, the Tempest sends a “message” to the PBA when to start charging and when to stop charging.

Where is the computer chip (or whatever it is) located in the PBA? Is it in the “wafer” near the tempest or is it located in the battery compartment?

I am trying to figure out some unexpected behaviors.

It is in the battery compartment. The wafer is merely part of the “extension cord.” If the power is from an external source the Tempest sensor will basically stay at full charge. On battery, it is supposed to charge up then wait to charge again until the Tempest battery voltage drops to somewhere around 2.4V and then charge up again.

thanks… that explains a lot.

I had issues with constant charging with the PBA.

I replaced the tempest (warranty) and the PBA but did not think the battery compartment was a “smart” one… .so I left it the same compartment after the replacement. Had the same problem. When I replaced the compartment… it now seems to be working…

Thanks again.

So the PBA will recharge the Tempest battery to its full level and then stop recharging until the Tempest battery drops back below some minimum level.
That’s if the PBA is powered by lithium batteries.

Over the weekend I connected the PBA (powered from 240V) to one of our Tempest stations, and the battery that was already at critical limits started charging properly.

However, since then, the battery in the Tempest is still at 2.81 Volts.
Does this mean that if the PBA is powered from using the AC adapter (240V) the battery in the Tempest somehow gets disconnected and the Tempest is permanently powered directly from the PBA?

I guess it would be logical, so as not to unnecessarily repeat the charging cycles of the battery in the Tempest…

YES. when connected to a power source… it will maintain max voltage.


I have mine with a smart plug so I just give it a boost (remotely) for 2& a half hrs when I want (during gloomy weather). So when it’s about 2.5V it’ll go back up over 2.6V.

The battery in the Tempest is not disconnected in this scenario. The battery is always connected. It is merely that the discharge rate of the battery is at zero once it reaches full. The net effect is that the energy from the booster goes to powering the Tempest while the battery is held at full charge.

I have a dilemma, and the advice would be good.

I have one of our Tempest stations now connected via PBA to a permanent 240V mains supply over the winter and dark days. The Tempest voltage is held consistently at 2.81V.

And now that the days are brightening up, I wanted to put the PBA back in the drawer to leave it for Tempest power.

But what if I left the PBA still connected to the Tempest? With permanent external power, the current from the PBA goes directly to the Tempest electronics, and the internal battery is kept fully charged.

And wouldn’t it be even better to connect the PBA via a smart socket, which I would only turn on the PBA when the voltage (bad sun conditions) of the Tempest internal battery drops to some threshold level. And what kind? To keep the Tempest from going into power saving mode.

I have the ability via Home Assistant or Homematic (I can see the “Weatherflow Voltage Tempest” value in both systems) to turn the PBA on or off in this way, and I would like to maximize the efficiency and life of the internal Tempest battery using a PBA controlled in this way.

So does it make sense to control the PBA in this way and let the Tempest battery continuously discharge and recharge, or is it better to leave the PBA permanently on and leave the 2.81V on the internal battery.
Or disconnect it completely on good sunny days?

Does anyone have any experience?

A little lost here. I thought the circuitry was that the PBA boosts (charges) the battery when there’s not enough solar to keep it full enough. So at the time of year with max solar that is enough to charge the battery, wouldn’t a PBA that is still plugged in yet actually be doing nothing ?

In other words, no need for a smart plug or to unplug the PBA at all. The solar is handling the load just fine and when the PBA needs to boost later in the year, it’ll take over as needed.


No, when on external power the PBA keeps the Tempest battery topped up. See https://help.weatherflow.com/hc/en-us/articles/4414460312603-Power-Booster-Accessory. It states that using an, “Auxiliary power supply will keep the Tempest device’s internal battery fully charged.”

I’m not sure why WF didn’t just use the same algorithm used when internal batteries are installed.

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There is a range that the booster will charge. (This is from memory, so please verify for yourself) It stops charging at 2.8 and will not start charging again until 2.45ish. These ranges only are valid once the firmware is updated to support the booster, so far you need to submit a support ticket when you get a booster so the firmware will get updated.

That is only when using internal batteries. Both the link I shared above and my own experience agree.

@dsj @eric

This is a misunderstanding of the function of the PBA.
When using a PBA permanently plugged into the mains (240V in the EU), the Tempest battery voltage is permanently maintained at 2.81V (in my case). That cycling only applies to using the PBA in power mode with a set of AA batteries (and that’s not my case).

And that’s my question, whether it’s ideal for the Tempest battery to be maintained at that sustained peak of 2.81V without discharge cycling. With a smart socket, plugged in before the PBA, I could achieve similar charge cycling of the Tempest battery, even when powered from 240V, as if it were being charged from a PV or a PBA with AA batteries.

I will add to my original question that I am asking what is best for the Tempest’s battery life, and of course taking into account that the Tempest does not switch to power saving mode.

And I repeat, with this specific station of ours, I can have the PBA connected year round via a permanent 240V supply - I can control that from the home automation system.

I don’t think this type of battery has any type of memory effect. 2.8V is still at some margin from what it can take as maximum (think we’re hovering around 80%).
Doing a cycle from time to time won’t harm neither (excessif cycling is what degrades batteries over time).
I’d say keep it on AC and maybe from time to time let it do a cycle (rather as a test to be sure it is still ok like everyone does with UPS systems).

And for the record, on AC the Tempest will be topped up and stay there (micro charges if the sun doesn’t shine)
On batteries it is supposed to cycle between +/- 2.42V and +/-2.6V if the sun can’t keep it above 2.42V.