Encoders for the elevators of the future:
KCI 419 Dplus and LINA 200

In the near future, cable-based elevator technology will no longer need microswitches for brake release monitoring. That’s because the new HEIDENHAIN KCI 419 Dplus rotary encoder for elevators provides position feedback for elevator motor control as well as additional data for brake monitoring.

In the more distant future, elevators will even run without cables. At interlift 2019, HEIDENHAIN will be showcasing an encoder solution for this as well: the LINA 200 absolute linear encoder.

HEIDENHAIN at interlift 2019 in Augsburg

Press Release

The KCI 419 Dplus rotary encoder for elevators: two-dimensional was yesterday

The new KCI 419 Dplus not only offers greater availability and safety; it also significantly reduces the time and effort necessary for installation, cabling, adjustment, and maintenance. The following capabilities are integrated in this device:

  • Motor feedback
  • Brake release monitoring
  • Wear indication data
  • Temperature monitoring
  • Online self-diagnostics
  • Digital data transmission

In addition to transmitting rotational position values, the KCI 419 Dplus inductive rotary encoder for elevators also measures axial motion. When mechanically coupled with the armature plate of the brake, the KCI 419 Dplus can detect the brake stroke. Based on this information, the subsequent electronics can determine the state of the brake (released or engaged) and the amount of brake wear.

By virtue of its direct proximity to the motor and brake, the KCI 419 Dplus rotary encoder for elevators also provides meaningful temperature monitoring data without the need for additional sensors. These temperature data can then be used to infer the presence of malfunctions.

Because all of these parameters are transmitted on a single cable via the purely digital EnDat 2.2 interface, overall system cabling is greatly simplified. Further benefits include improved remote monitoring and predictive maintenance capabilities.

In addition to these completely new innovations, the KCI 419 Dplus also includes all of the familiar strengths of classic rotary encoders from HEIDENHAIN. Its inductive scanning method is highly immune to contamination and vibration, and is renowned for its operational reliability.

LINA 200: the absolute linear encoder for a future where elevators have no cables

Envision an elevator car not pulled by cables while capable of both vertical and horizontal travel—HEIDENHAIN is offering the encoder technology to make this possible: the LINA 200 absolute inductive linear encoder. It consists of two tracks with different signals periods, from which the absolute position value is then calculated.

U-shaped design for mechanical sturdiness and robustness of encoder signals

A special feature of this scale is that the two tracks are not located in one plane; instead, they face each other. The resulting U-shaped scale allows the measuring standard to be scanned from two sides. At the same time, a double-wall design protects both the graduation and the scanning process from mechanical and electromagnetic interference. This structural configuration also combines maximum stiffness with low weight.

Graduation carrier of LINA 200

  • Attached to the elevator cabin
  • Overall length: 2400 mm
  • Four segments, each with a measuring length of approximately 600 mm

LINA 200 scanning heads

  • Arranged in a cascading pattern in the elevator shaft
  • Continuous position feedback over the entire travel distance
  • Generous guideway tolerances of ±5 mm and ±4 mm
  • Measuring step: approx. 2 µm

Performance data

  • Traversing speed tested in an elevator shaft: 6 m/s
  • Traversing speed tested in a laboratory: 18 m/s

The LINA 200 thus delivers reliable, highly accurate position feedback for the cableless elevator’s motor control. Yet it also provides sufficiently wide tolerances for real-world mounting inside the elevator shaft and for the compensation of building displacement. At low speed, as well as during the deceleration and acceleration phases before and after a stop, the high-resolution position feedback (18 bits) at a measuring length of approximately 600 mm ensures very comfortable and gentle motion.

Read the LINA 200 technology report

Reliable data transmission via EnDat for high dynamic performance and passenger comfort
The scanning head signals of the LINA 200 are so robust and reproducible that the diagnostic values for signal quality defined in the EnDat protocol can also yield information about whether the guide rails are within tolerance. The LINA 200 thus serves not only as a linear encoder but also provides data for continuous diagnostics and condition monitoring of the larger mechanical system. As a result, lateral deviations during operation can be detected.

The high-accuracy position values are transmitted purely digitally to the subsequent electronics via the EnDat 2.2 interface. In this particular application, however, EnDat 2.2 provides another important and safety-relevant benefit pertaining to the strong magnetic fields that surround linear motors: the EnDat 2.2 interface features high electromagnetic compatibility and, unlike conventional analog signals, ensures reliable data transmission even in this kind of environment.