The Strap charging process may be interrupted in the following circumstances:

1. Changes in the charge current. 

2. Power spikes. As a precaution, make sure you are connected to a stabilized charger (mobile phone charger or similar). 

Please note that if you are charging Woojer Strap from a PC, it may stop charging if the current from the PC is too low

or alternatively, if your PC turns to "Sleep Mode".

3. In certain cases there will be period of 60 to 360 seconds prior to the end of charge, during which there may be no LED indication. At the end of this brief period the Strap will indicate “end of charge” with a green LED light.