An elevator installation has an elevator car carrier that can be displaced in a travel space, a first elevator car arranged on the carrier in an adjustable manner, and a second elevator car arranged on the carrier. A drive unit on the carrier drives a traction device to adjust the first elevator car relative to the carrier. The traction device forms a closed loop and is guided over a drive roller and at least one guide roller, which rollers are arranged on the carrier. The guide roller is displaceable on the carrier to set tensioning of the traction device.

In a system and method for an automatic rescue operation of an elevator car in an elevator system, the elevator system includes a hoisting machine and a battery-operated rescue drive device configured to provide power signals to the hoisting machine and/or hoisting machinery brakes. A load sensor is configured to gather elevator car load information, and the rescue drive device is configured to select, based on the elevator car load information, a first rescue run or a second rescue run.

In a system and method for an automatic rescue operation of an elevator car in an elevator system, the elevator system includes a hoisting machine and a battery-operated rescue drive device configured to provide power signals to the hoisting machine and/or hoisting machinery brakes. A load sensor is configured to gather elevator car load information, and the rescue drive device is configured to select, based on the elevator car load information, a first rescue run or a second rescue run.