Download to - Automatic Doors

Technician’s Service Guide
Overview
In order to service, repair or maintain any product or equipment you must first understand how
it operates, what is connected to it and what these peripheral devices such as sensors
switches etc do and how they work.
1.
Auto door controller – it accepts inputs such as signals from sensors, switches,
inbuilt time clocks or software programmes and other systems such as fire alarms
and security systems. It then decides what the outputs should switch on and off
based on the signals and commands it gets.
Some of the outputs are power to the motor, power to the lock, power to the buzzer, power to
relays such as door status relay or people counter etc.
Power to accessories such as sensors are outputs via the control board however these come
directly from the voltage source via the onboard power supply. So strictly speaking we should
consider this as a separate source not a controlled output.
2.
3.
4.
5.
Motor – type permanent magnet DC motors (please research and understand how
they work). Essentially if the nominal rated dc voltage is applied the motor will turn
in one direction at the rated speed. When this voltage is reversed it will turn the
opposite way. When the voltage applied is reduced it will run slower. So in theory a
zero voltage will produce no speed and zero torque, 50% of the nominal voltage
will roughly produce 50% of the full speed but the torque may not be 50% of full
torque. It will not be 100% torque either. The torque will be somewhat less but can
be determined by its torque speed characteristics data. For this exercise we just
need to be mindful of the fact that the speed and torque has a relationship and that
the lower the speed hence the applied voltage the lower the torque is.
Sensors – these are either detection sensors or safety sensors. Essentially they
are switches that close and open via relay contacts for example. Depending on
where they are connected to, the controller takes the appropriate actions.
Control switches such as push button or mode switches again as in 4 above.
Control signals from security system or fire alarms again are similar to 3 & 4.
Mode Key Pad
This is purpose designed to communicate with the controller and is an interface between us
and the control board. The controller communicates to us and we communicate to it via this
device. Key pads software must match the controller software. The door may not operate
correctly if the key pad and controller is mismatched.
LS220B LS300 LSW LP
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V-500 2013