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
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 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
- 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.
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 features high electromagnetic compatibility and, unlike conventional analog signals, ensures reliable data transmission even in this kind of environment.
HEIDENHAIN solutions for conventional elevators:
Encoders for main motors, shaft copying systems, and doors
HEIDENHAIN rotary encoders are rugged, reliable, and high-resolution. For years, these characteristics have made them proven and reliable solutions for motor control and position measurement in conventional elevators. Not only do they meet growing elevator-industry demands for fast speeds, large travel heights, compact designs, and low operating costs. They also ensure optimal ride comfort, including smooth destination approach, steady acceleration, gentle braking, and precise arrival for a comfortable, jerk-free experience.
Rotary encoders for elevator motor control
HEIDENHAIN rotary encoders for elevator motor control offer the following characteristics:
- Excellent signal quality
- High accuracy
- Rigid shaft connections
- Easy installation
- High mechanical natural frequency (with expanding ring coupling)
- Wider operating tolerances (with plane-surface coupling)
With tapered shaft (1:10 ratio and 9.25 mm in diameter):
All rotary encoders of this series are available with an expanding ring coupling or a plane-surface coupling.
For hollow through shafts (up to 50 mm in diameter):
For detailed information on individual series and models, visit these links:
Rotary encoders for digital shaft copying
For properly timed, jerk-free braking and exact positioning of the elevator car, the car's position must be accurately measured and forwarded to the control. Absolute rotary encoders are the logical choice for this task, bringing distinct benefits to digital shaft copying:
- Constant availability of the car’s absolute position, even after a power outage
- Rapid destination approach thanks to constant availability of the actual position
With a mounted stator coupling:
For particularly high shaft loads reaching up to 150 N axially and 350 N radially, the EQN 400 is also available with a bearing assembly. This feature decouples the encoder’s bearing from applied forces and prevents overloading.
Rotary encoders for door motors
The fast and perfectly timed operation of elevator doors enables shorter stopping times, thereby increasing traffic performance. Accurate and dynamic position measurement is key to attaining this. HEIDENHAIN rotary encoders for door motors provide the necessary speed and position feedback in a compact design, featuring an outer diameter of less than 40 mm for all encoders.
With a hollow through shaft (up to 8 mm in diameter):
With a blind hollow shaft (6 mm in diameter):
Easy implementation with EnDat
EnDat is the ideal interface for digital drive systems and position control loops using position encoder feedback. In particular, the interface’s purely serial design offers numerous benefits of great value to applications in the elevator industry. Purely serial data transmission via EnDat is:
- Wide selection of encoders from various suppliers
- Simple cabling and integration of additional sensors
- Short cycle times
- High bandwidth
- Transmission of position values and sensor data
- Extensive system monitoring for Industry 4.0
- Electronic ID label for automatic system installation
- Online encoder diagnostics • Storage of operating status data
- For safety-related applications with up to SIL 3
Implementation is made easier with the EnDat Master, or in the elevator industry, the EnDat Master Mini. Designed specifically for fast and cost effective implementation, it handles communication between the purely serial EnDat encoder and the higher-level application. For more information, see the Implementation Guide.