Champion Victorian trainer Darren Weir faces serious charges relating to electronic devices found in his stables at Ballarat and Warrnambool and Racing Victoria stewards have asked him to show cause why he should be allowed to continue his operation.

RV stewards issued the charges on Friday, two days after they and Victoria Police officers from the sports integrity unit raided his stables at Warrnambool and Ballarat.

His assistant, licensed trainer Jarrod Weir who runs the Warrnambool stable, have both been charged with possession of the devices, commonly known as jiggers, which are designed to give a horse an electric shock.

The two have also been charged with failing to give evidence at a stewards inquiry on Thursday and with conduct prejudicial to the image of racing.

RV said both had been invited to show cause via a telephone hook-up on Friday afternoon why stewards should not invoke their powers to refuse nominations from the stable.

A third man, stable employee Tyson Kermond, has been charged with failure to give evidence at the inquiry.

A five-time Melbourne premiership winner, Weir runs the biggest stable in the country with more than 600 horses on the books and dozens of staff at both locations.

His biggest win came in the 2015 Melbourne Cup when 100-1 chance Prince Of Penzance claimed a famous victory for jockey Michelle Payne.