Operating Principle - Automatic Systems BL 227 EVO Technical Manual

BL 227 EVO

5.5. OPERATING PRINCIPLE

Items referred to in this section can be seen on the images ( Chap. 5.4. Location of components, page 10)
Arm opening (8) is controlled by a keyswitch, a push-button, a radio transmitter, a command sent over the network connection,
detection loops buried in the roadway, or an external control device (tollbooth, card reader, management centre, etc.).
Closing is controlled in the same way, or automatically via a timer.
The processing of these commands may be made contingent on external information to be received by the barrier. For example,
closing is not allowed if a vehicle is detected in the obstacle's path (information received from a detector), or opening is not
allowed if the parking lot is full (information received via another device).
The movement initiated by the gear motor (17) is directly transmitted to the arm by the main shaft Ø75 (7).
The speed of the arm, controlled by the variable frequency drive (9), is adjustable for both opening and closing movements.
Movements are factory-configured to provide fast acceleration and slow deceleration at the end of the movement.
The control logic (13) coordinates the barrier's activity: management of movements and options, input and output information
processing, etc. This information can be downloaded and processed by an external terminal (not provided by Automatic
Systems).
A compensating spring (24) acts as a counterweight. It helps the motor during opening and closing based on accessories and
lengths (models without automatic raising of the arm in case of power failure).
For barrier models with automatic raising of the arm in case of power failure, the spring tension is increased to ensure that it
can raise the arm by itself in the event of a power failure.
Maintaining the arm in its two extreme positions (open and closed), as well as after a Stop command is achieved by means of
an electromagnetic brake: Normally Closed Brake (= closed when idle, i.e. not powered on), energized during arm movement
to release the arm.
For models with AVR (with automatic raising) (optional), the electromagnetic brake is of the NO type (= open when idle, i.e. not
powered on), energized in the two extreme positions (open / closed) to ensure locking of the arm.
The BL 227's optional swing-off jaw allows arm swing-off (swivelling of the arm away from
the fixing jaw) in the event of an impact. This prevents damage to the barrier and the vehicle
hitting it.
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