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Product Features
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Product Features
LIMAX44 RED is an absolute shaft information system which is used for the positioning of elevator cabins. It is
available in two different versions. In the unguided version, the measuring system consists of two components:
Magnetic tape and sensor. The semi-guided version requires an additional presence detector to monitor the
correct tape position.
The tape carries the unique position information as a magnetic code. In the unguided version, it is glued directly
onto the guide rail of the elevator. In the semi-guided version, it is mounted freely suspended in the shaft and is
guided along the sensor with a plastic guiding rail. The measurement is always contact free. The guiding only
serves to keep the tape within a defined distance from the sensor.
The sensor reads the magnetic code from the tape and then provides the evaluation unit connected downstream
with the position information.
The presence detector makes sure that the magnetic tape is in the intended position and remains there – after
all, various safety functions depend on the position derived from the tape.
In the case of unguided installation, this monitoring can be omitted, as it can be assumed that the magnetic
tape does not shift in its position.
According to EN 81-20/50 and previously EN 81-1/2 the use of programmable electronic systems in safety-
relevant applications for lifts (PESSRAL) is allowed. LIMAX44 RED is designed and certified for those applications.
The sensor is designed to be used as a safe sensor together with a safe evaluation unit (like for example in
ELGO´s LIMAX44 Safe) or directly with a safe controller unit. Together, the entire system is able to fulfil the safe-
ty functions in the elevator according to EN 81-20 and EN 81-21. The product is compatible to the previous
norm EN 81-1/2 and may be used as modernization solution or as measuring range extension in existing instal-
lations. Fig. 1 shows the use in the two possible areas of operation as unguided variant, Fig. 2 as semi-guided
variant.
The magnetic measuring principle is distinguished by its extremely high robustness. Dust, dirt and moisture do
not affect the measurement in any way. Furthermore, as smoke and increased temperatures do not have any
impact on the measurement, LIMAX44 RED is especially suitable for firemen’s lifts. Thanks to its material compo-
sition, the tape itself is resistant enough to the rough conditions during the installation and operation of eleva-
tors.
Another advantage of the system is in its easy and flexible mounting. The installation itself can be carried out by
an expert in just a few minutes. Depending on the space available, the system can be installed almost anywhere
in the shaft. Since it requires little space, LIMAX44 RED is also suitable without restrictions for retrofitting and
modernizations.
The LIMAX44 RED is able to cover lifting heights of up to 786 meters and speeds up to 16 m/s.
Overview of features:
Robust measuring principle for rough conditions
Easy and flexible mounting
High accuracy and repeatability
No slip
Absolute position always directly available – no reference journey even after long power failures
Compatible with many established position controllers with absolute encoder interface.
High speeds possible
