Can you help me identify the pads for charging the battery?

I’ve seen the posts about a DIY charging solution but I can’t figure out which of the pads at the base are positive and negative and don’t want to assume there’s reverse polarity protection so does anyone know which of the pads on the base are + and -? I know it’s the two outside pins used to charge the battery but not the polarity . Picture attached. Thanks.

Here’s an image from back around May of 2020 that will show which pogo pad is for Pos and Neg (ground).


When a Power Booster Accessory (WF-PBA01) is snapped onto the bottom of a Tempest. . .the pogo pins will line up eXactly with the corresponding pogo pads on the bottom of the sensor device.


Thanks! You’re the best! Which thread was that in? I swear I read a lot of threads before asking.

The image was clipped out from the original “Tempest Field Tester” group. . .which has long been archived and no longer accessible except by “WF Staff”.

1 Like

All good. Thanks again for your help.

Here is a little more context to the original post. It was in response to a field test Tempest which has a very bad charging issue and was before the power saving modes were introduced. Note the last sentence.

1 Like

Thanks for the extra context. That last line is interesting because on the base of my device it says this so I was only going to feed it 2.8V.

I wonder if that is the minimum input voltage. It is likely that the solar panel output is up to 5V so that is what the charge controller can handle. I would just watch the current as you increase the voltage. If 3V is all you need, stop there, for example.

I just tried a connection to the pogo pins that supplied 4.5v from an old AC adapter I had laying around, didn’t have much luck. Then I injected the voltage into one of the connections for one of the solar panels. It brought the LTO Cell up to 2.8V, and then held it there.

That is the problem. It needs to be DC, as indicated in the picture. Only the power box of the PBA can take either AC or DC.

Sorry, I should not have assumed that everyone would know what an AC Adapter is:
An AC adapter, also known as a power adapter, is a device that converts alternating current (AC) power from a wall outlet into direct current (DC) power that can be used by electronic devices. The purpose of an AC adapter is to provide the correct voltage and current required by a specific device, allowing it to operate or charge its batteries.

AC adapters are commonly used for various electronic devices such as laptops, smartphones, tablets, cameras, and other gadgets that require a power source. They typically consist of a plug that can be inserted into a wall outlet, a power cord, and a connector that plugs into the electronic device. The adapter contains circuitry to regulate the electrical output and ensure it meets the specifications of the device it is powering.

AC adapters come in different shapes, sizes, and voltage/current ratings, so it’s important to use the correct adapter for each device to prevent damage. Some adapters are designed with interchangeable tips or connectors to make them compatible with a variety of devices.

I know what an AC Adapter is. There are two types, those which output AC and those which output DC. You didn’t say and I mistakenly assumed AC output.

Oh, I see now, you meant you assumed I used a ‘Transformer’. Again, I should not have assumed all readers would make the distinction between transformers and adapters, thanks for clarifying, this is good to know in the future.

An AC adapter that converts AC (alternating current) to AC is typically referred to as a power converter or AC power transformer. Unlike the more common AC-to-DC adapters, which convert AC power to DC power, AC-to-AC adapters are designed to change the voltage level or modify the characteristics of the AC power, such as converting between different voltages or providing isolation.

These devices can be called transformers or converters depending on their specific functionality. Transformers are commonly used when the primary goal is to change the voltage level of the AC power, while converters may include additional circuitry to modify other characteristics of the power, such as frequency or waveform.