An elevator includes an elevator car and lifting machinery including a traction sheave, an electromechanical machinery brake, and an electric motor having a rotor. The traction sheave, the electromechanical machinery brake and the rotor of the electric motor are connected via a shaft, whereby the lifting machinery moves the elevator car upwards and downwards in a vertically extending elevator shaft controlled by a main control unit. The direction of rotation and the rotation speed of the rotor of the electric motor is detected with a sensor, the amplitude of the brake current provided to the machinery brake is measured, the amplitude of the brake current is increased until a first moment when the shaft and thereby also the rotor of the electric motor starts to rotate, which is detected by the sensor, the brake current is disconnected momentarily at the first moment, the torque acting on the shaft and the corresponding load in the elevator car at the first moment is determined based on the measured amplitude of the brake current at the first moment, whereby said torque is used in the main control unit for controlling the lifting machinery.

An exemplary brake device includes a brake element configured to apply a braking force to resist rotation of an associated component. A mounting member is configured to mount the brake device to a stationary surface. The mounting member is at least partially moveable relative to the stationary surface responsive to a torque on the brake device. A sensor provides an indication of a force associated with any movement of the mounting member relative to the stationary surface responsive to the torque.

A method and system for reducing rollback in a counterbalancing system as a holding brake is released is disclosed. A limited amount of movement of a drive shaft is present in the holding brake. A motor drive provides current to the motor with the holding brake set such that a torque is applied at the drive shaft. The current is controlled to generate torque in both directions. The limited amount of movement in the brake may be used to determine a direction and magnitude of torque required to support a mechanical load being applied to the motor. The motor drive then provides a current to generate the necessary torque required to support the load prior to releasing the holding brake.

A method for determining a lead torque of an elevator system involves: generating control commands controlling an electric motor so that an elevator car coupled to a counterweight performs at least first through fourth test runs, wherein the car is moved from a first to a second position and back in successive runs and is loaded in the third and fourth runs with a weight; during movement of the car receiving current measurement data of current flowing through the motor and height measurement data indicating a height of the car; calculating at least one parameter of a calibration function defining a relationship between the current, the height, and the weight using the measurement data to obtain at least one calibration value; and calculating an adaptation value wherein the counterweight is adapted to be in equilibrium with the car using the at least one calibration value.

An elevator includes an elevator car and lifting machinery including a traction sheave, an electromechanical machinery brake, and an electric motor having a rotor. The traction sheave, the electromechanical machinery brake and the rotor of the electric motor are connected via a shaft, whereby the lifting machinery moves the elevator car upwards and downwards in a vertically extending elevator shaft controlled by a main control unit. The direction of rotation and the rotation speed of the rotor of the electric motor is detected with a sensor, the amplitude of the brake current provided to the machinery brake is measured, the amplitude of the brake current is increased until a first moment when the shaft and thereby also the rotor of the electric motor starts to rotate, which is detected by the sensor, the brake current is disconnected momentarily at the first moment, the torque acting on the shaft and the corresponding load in the elevator car at the first moment is determined based on the measured amplitude of the brake current at the first moment, whereby said torque is used in the main control unit for controlling the lifting machinery.

A method of startup from a resting state for a ropeless elevator system and a ropeless elevator system are disclosed. The ropeless elevator system may include a hoistway. The method for startup may include applying a thrust force on the brake, the thrust force generated by a propulsion system, detecting the thrust force on the brake, determining if the thrust force on the brake is greater than or equal to a requisite thrust force for startup, and disengaging the brake if the thrust force on the brake is greater than or equal to the requisite thrust force.

The invention relates to a method and an apparatus the invention is a method for automatic configuration of an elevator drive in a traction elevator comprising an elevator car, a counterweight, a traction sheave, an electrical motor and a plurality of elevator ropes arranged to hoist the elevator car in response to the electrical motor rotating the traction sheave. The method comprises obtaining a plurality of electrical motor parameters from a memory associated with the electrical motor. A drive computer unit determines a roping ratio of the elevator by driving the elevator a distance based on elevator position sensor information and determines a plurality of torque values required to hoist the elevator with a predefined starting acceleration when the elevator car is loaded with a respective plurality of different loads. The torque values per each load are stored to a memory of the drive computer unit.

An elevator system includes an elevator car and a drive unit. The elevator system also includes one or more power sources for providing power to the drive unit, a current sensor and a controller. The controller is configured to cause the current sensor to measure a current through the motor while the elevator car is held stationary at the landing by the motor and/or during an initial phase of the run profile, to determine an available power from the one or more power sources, and to determine a predicted power demand for the drive unit based on the measured current and one or more parameters of the predetermined run profile. The controller is also configured to determine whether the predicted power demand is greater than the available power from the one or more power sources.