Powering timers with USB
Posted: Sun Feb 18, 2018 9:22 pm
I just wanted to talk about something we started doing a couple of years ago. We run around 25 derbies a year on our Best Track and Microwizard P3 timer. We are always looking to streamline our process, so saving time by NOT running another extension cable just made sense. I've looked at using battery packs to power timers, but I never wanted to run into issues where I didn't have extra batteries and couldn't finish a race unless I ran an extension cord. Running 2 races in a day in 2 different venues means we need to be as portable as we can.
I found a $6 power converter http://a.co/jjWYo3k that increases the 5V power from a standard USB power brick up to 9V or 12V. Most of the commercial timers I've looked at will run on 9V or 12V.
The adapter has a 2.1mm barrel jack, but my timer uses 2.5mm. I need to just replace the cable end, but for the last 2 years this adapter has worked fine. http://a.co/1WBaglV
Plug the power converter into a $30 20,000mAh battery pack I already had http://a.co/eRVmcQF, and I'm able to run 10 races without going below 70% charge. It's easy to recharge every couple of weeks and lives in the bag with the laptop/printer we use for derbies.
The P3 timer has LCD displays instead of LED, so it has very low power draw. I've also used a Champ timer with the 12V converter version and it works great. In that case I just recharge more frequently, but still only after several races.
Hopefully this idea helps someone.
---pinewoodnut
I found a $6 power converter http://a.co/jjWYo3k that increases the 5V power from a standard USB power brick up to 9V or 12V. Most of the commercial timers I've looked at will run on 9V or 12V.
The adapter has a 2.1mm barrel jack, but my timer uses 2.5mm. I need to just replace the cable end, but for the last 2 years this adapter has worked fine. http://a.co/1WBaglV
Plug the power converter into a $30 20,000mAh battery pack I already had http://a.co/eRVmcQF, and I'm able to run 10 races without going below 70% charge. It's easy to recharge every couple of weeks and lives in the bag with the laptop/printer we use for derbies.
The P3 timer has LCD displays instead of LED, so it has very low power draw. I've also used a Champ timer with the 12V converter version and it works great. In that case I just recharge more frequently, but still only after several races.
Hopefully this idea helps someone.
---pinewoodnut