Briton Hamilton and his Mercedes AGM F1 W04 sped over the gravel at the end of the back straight, hitting the tyre wall head-on.
Feb.6 (GMM) On his first day of official running in 2013, Lewis Hamilton crashed the new Mercedes.
The 2008 world champion had done a few filming laps in the silver W04 on Monday, but Wednesday was his first real day of on-track work in the wake of his six years as a McLaren driver.
A team spokesman said the cause was a braking problem.
"He managed to slow the car with the front brakes but was unable to avoid the barrier. Lewis is fine," he said.
It is another blow to Mercedes, after Nico Rosberg's debut running on Tuesday was cut short by an electrical fire.
"This is really annoying," chairman Niki Lauda is quoted by Auto Motor und Sport.
"Yesterday we lost almost the whole day of testing, today again ..."