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Design and Functions
9.4
Door Zone Indication
LIMAX44 RED provides a function to indicate the door zones. This function shows whether an elevator is posi-
tioned within the door zone, even during a power failure. The location of the door zones is derived from the
flush positions of the different floors. These positions must be determined during the initial reference journey for
the evaluation unit. The positions of the floor levels are saved permanently and are available even after a power
failure.
NOTE!
In order to keep the indication of the door zones active for an evacua-
tion during a loss of the regular power supply, an emergency power
supply or a back-up battery is necessary to supply the sensor with ener-
gy.
The position of the floors must be transmitted from the evaluation unit to the sensor. Also, the evaluation unit
has to signal changes in the position of the floors to the sensor.
After the sensor is switched on, the door zone output is briefly switched to active. This enables a function check
of the downstream indicator lamp.
Further information:
Technical data of output
Protocol for alignment of floor positions
9.5.4, in the section on
floor information
under the respec-
tive interface
9.5
Connections and Interfaces
The following chapters will give you detailed information on the connections and interfaces
9.5.1
Power Supply
Normally, LIMAX44 RED is supplied with 24 VDC. In order to guarantee the functioning of the door zone indica-
tion for evacuation in case of a power failure, an external 12 V battery can be connected.
Switching between the two supply voltages has to take place outside the sensor and can be realized for example
with the following diode circuit:
Fig. 24: Possible circuit for supply by emergency battery in case of power failure
The sensor switches automatically between the two operating modes (
9.2) based on the applied supply volt-
age.
The pin assignment depends on the connection option and is documented in chapter
9.5.2
Door Zone Indication
For the indication of the door zones, a PNP-output is integrated in the sensor. It can be directly connected to a
light bulb or an LED for indicating the status.
The output is short-circuit-proof against GND (but not a24 V) and can be operated with max. 200 mA.
regular power 24 VDC
emergency b12 VDC
power supply sensor
