A carrier mounted on a cart for transporting a bag or a sack containing loose or granular materials. The solids are collected in a chamber having a bottom surface and a surrounding side surface. The first and second holding portions are electrically connected to each other via only the adjustment plate, due to the adjustment plate being sandwiched by a first side plate of the first holding portion and a second side plate of the second holding portion. Accordingly, when a busy service is deemed dead, the container manager can automatically re-start the service.