Recharging lights

By CyclingUKvolunteer
Twin USB light charging - most likely more slowly
Over winter, I find I’m recharging my lights more and more often. This is fine from home – I can use my laptop to charge both at once in order not to have to wait for one after the other before going to bed. But while touring, I have only a compact camera charger. I would need two chargers to do both lights simultaneously. I’ve seen twin chargers for phones and tablets but lights are not mentioned. My camera charger output is 5V 800mA. Is this optimum for bike lights?

Christopher Lycett

The fine detail of USB technology occupies a lengthy Wikipedia page, but the salient points are that USB port output is a nominal 5V, which will charge any device supplied with a USB connector cable, and that USB power adaptors supply current as required by the charging device, generally from 500mA up, in some cases, to 2A, per port. Current – in amps – determines the rate of charging, and a battery’s capacity the time taken to charge it at a given rate. The Exposure Strada 800’s own dedicated charger supplies 1.5A, so two Strada 800 lights connected to a twin port charger capable of supplying 3A should charge in the usual time. Depending on the lights you use and the time you reach your digs, a 2A twin charger might still charge your lights by bedtime. 

Richard Hallett

​​​Cycle’s Technical Editor

Q&A Lights Technical advice

This Q&A was published in 'Cycle' the magazine for members of Cycling UK. To contact the experts, email your technical, health, legal or policy questions to [email protected] or write to Cycle Q&A, PO Box 313, Scarborough, YO12 6WZ

Further reading