SB series
User’s manual
27
9.6 OVERRIDE
This function makes it possible to procure a condition of total bypass,
should it be necessary to start up the machinery even if one or more
rays have been interrupted by the material. The objective is to free the
protected area from any material that has accumulated in front of the
barrier, for example further to a fault in the machinery’s cycle.
If we imagine a
pallet
has stopped in front of the protected area, it will
not be possible to restart the conveyor belt because the barrier detects
one or more rays have been interrupted and therefore will not close the
outputs; therefore the area controlled cannot be liberated.
However, it can be liberated if the
override
function is enabled.
This function is active for all barriers with the LMS connected, as
described in section 3.
9.6.1
ENABLING THE OVERRIDE FUNCTION
x
Switch the appliance off.
x
Switch it on again and press the
test/restart
button within 5
seconds, keeping it pressed for at least 5 seconds.
x
The
override
function is now enabled. The LMS flashes to signal
the exclusion of the barrier.
x
The maximum duration of the
override
function is 120 seconds,
after which the barrier is restored, even if the button is kept
pressed. Naturally, if the button is released before this, the
override
function will terminate immediately.
9.7 FLOATING
BLANKING
9.7.1
DEFINITION OF
FLOATING BLANKING
Floating Blanking
means the permanent masking of a certain number of
optical units in a set part of the sensitive area of the barrier. The maximum
quantity of optical units that can be masked depends on the total number of
the optical units in the system.
This cannot be more than 30% of the total number of optical units; however
if 30% corresponds to more than 20 optical units, the system will cap the
number of optical units at its maximum number of 20.
The following examples can help to understand:
Example 1:
total optic rays:
= 102
optic useful for blanking = 31
The zone can be higher than 20ray, but the unit can only mask 20 rays!!!
SB series
User’s manual
28
Example 2:
total optic rays:
=24
Optic useful for blanking
= 7
The maximum maskable zone is 7 rays.
9.7.2
MEMORISATION PROCEDURE FOR FLOATING BLANKING
The object is memorised as follows:
1. Switch
the
barrier
off.
2.
Put the object for
floating-blanking
into place.
3.
Connect the MUTING A input to 24Vdc. The TEST/RESTART contact
must be closed.
4.
Restore the barrier’s power supply.
5.
Now supply the MUTING B input with 24Vdc.
6.
The barrier signals successful memorisation of the object by the
flashing of the LOWER led which thus confirms acceptance of
floating-blanking
. If the led does not flash at this point, it means that
the object takes up an amount of optical units which is above 30% of
those physically present; it should however be remembered that the
maximum limit is 20 optical units.
7.
Now disconnect the two MUTING A and MUTING B wires from
+24Vdc.
8.
The barrier works normally and signals the
floating-blanking
operation
by the flashing of the yellow LOWER led on the receiver.
PLEASE NOTE:
The last optical unit opposite to the connector side
cannot be used
with the
floating-blanking
function, as it is the optical unit for the synchronism between
the two barriers.
If
floating-blanking
memorisation was completed without the object, and thus
with the rays free, the LOWER led will not flash at the end of the process as
the entire bar is operational: this is a simple way to reset the
floating-blanking
function.
If the object memorised, for any reason, is removed or occupies a lesser
number of optical units than in the memorisation process, the barrier will
signal the anomaly and the outputs will be de-energized. The LOWER (yellow)
led and BREAK (red) leds will flash to indicate this particular status. It is
possible to exit this error status by pressing the TEST/RESTART button
provided the object has been restored.
