Safeline STANDARD SERIES Instruction Manual Download

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keys such that the reject mechanism operates just
as the front/leading edge of the pack reaches the
centre of the reject device.

When set – press ENTER once

10) The reject shift will be adjusted as the last
operation so do not worry at this stage about the
reject mechanism operation.

If no further adjustment is required press ENTER
again. The display will change showing the type of
timer and asking the question

tm3 Gated? Yes /No

10) Select ’Yes’ displays reads

tm3G Sync Shift ###

ETC Window Shift ##4

NOTE:–

a) Always set the window shift first.

b) A metal test piece is not required to set these
two parameters.

c) The position on the conveyor of the photogate
sensor should always precede the reject mechan-
ism. Ensure the sensors do not effect the operation
of the metal detector itself by infringing the
metalfree zone limitations.

At line speeds of 61m/min (200ft/min) or greater,
the sensors must not be positioned too close to the
reject device, ensure a minimum distance of 0.5m
(1.5ft).

Adjust the height and alignment of the sensors
so that all packs break the beam at the same
leading edge position irrespective of the type or
size of pack.

d) When the Gated option is selected the Reject
Shift is changed from being controlled by the speed
sensor to being controlled by the internal time clock
with units in seconds. A pre-set time setting of
100ms is the initial setting of the Reject Time and
this should be sufficient to allow the Window Shift
and the Sync Shift to be set first, before trimming
the ’Reject Time’.

12) To set ’Window Shift’
Press key adjacent to ’Window Shift’.Display

Shows CAL for 5 seconds after which ‘RUN’
Appears.

With run displayed pass a pack of the correct size
and orientation along the conveyor making sure
that it is square on to the conveyor or with a skew
angle typical for the line. The detector will
automatically set the window shift based on the
length of the pack.

The window shift can be measured several times to
assess the effects of skewing of the pack simply by
repeating the above procedure.

NOTE:–

a) CAL is calibrating the photo sensor so that
either a light energised or a dark energised sensor
can be used.

b) Ensure that during the CAL period there are no
inadvertent interruptions of the photo-beam.

c) The detector head is always pre-set to operate
with a NPN photo-sensor but it can be switched
(internally) to operate from a PNP photo-sensor.

Both photo-sensor and speed sensor must be the
same output type, NPN or PNP.

d) The Window Shift is entered into memory
automatically and a correction is applied by the
microprocessor to provide a window that overlaps
the pack at the front and rear by one half pack. This
ensures an accurate and reliable reject action
regardless of where the metal contamination is
within the pack.

e) The window shift is automatically extended for
large pieces of metal contamination or for more
than one piece of metal contamination.

13) To set Sync Shift

Sync Shift is the distance measured in shift pulses
from the front edge of the pack interrupting the
photo-beam to the pack being in its optimum reject
position.

Press the key adjacent to ’Sync Shift’.

Pass the correct size of pack along the conveyor.

Both the detection light and the buzzer are
operated continuously during this procedure, and all
packs will now operate the reject mechanism even
without having a metal test piece.

Adjust the Sync Shift setting until the pack is
accurately rejected.