What Does This Mean? Low Battery Readings on the Joule GPS
Ever wonder how to tell if your computer or PowerTap hub is running low on batteries? Look no further than your Joule or Joule GPS - it'll notify you when something on your bike is low on batteries.
The Joule GPS is a great training tool to see how you are performing in your workouts. However, like most electronics, its batteries can drain down to zero — and no one wants to get caught without their training data.
The Joule GPS low battery pop-up notice is formatted this way:
<Device> can be one of five products on your bike
- Power = Your powermeter battery is low and batteries need to be changed
- Joule = Your Joule GPS battery is low and needs to be charged
- Speed = Your speed sensor batteries are low and need to be changed
- Cadence = Your cadence sensor batteries are low and need to be changed
- HR = Your Heart Rate Monitor battery is low and needs to be changed
For example, if your PowerTap hub battery is low you would see "Power Low Battery".
Most coin cell batteries, when new, are around 3.0-3.2 volts at full capacity (the CR2032 size, in most sensors). Low battery notices usually occur when the battery voltage drops to 2.6 volts, and the PowerTap hub will notify you of low battery at 2.5 volts. Winter cold months can cause artificial low battery messages, due to conductivity. This is why you may see more low battery warnings in the winter.
For the Joule, the "Low Battery" message is displayed at the lower end of the screen. When the hub battery is low, the message "Lo Batt. Pwr" appears at the bottom of the screen. The Joule low battery message format is similar to the Joule GPS – "Lo Batt. <device>" where <device> can be Pwr, Cad, HR.
Joule low battery warnings "Lo Batt <device>:
- No <device> shown = Joule battery (see image below)
- Pwr = Powermeter battery
- Cad = cadence sensor battery
- Spd = Speed sensor battery
- HR = Heart rate monitor