Safeline STANDARD SERIES, Инструкция по эксплуатации

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2) Enter access code.
3) Select lowest available product number (01 to 20).
4) Manually set phase to 0000.
5) Adjust sensitivity so that the peak signal from the
product gives just less than full scale indication on the LED
bar graph display. If the signal is very large, such that zero
sensitivity does not reduce the product signal to less than
full scale indication on the LED bar graph, it may be
necessary to reduce the power level (see Power Drive in
’Programmable Settings’).
6) To find the null point, change the phase setting to
0500 and observe if amplitude of product signal indicated on
the bar graph display reduces. Repeat the process
increasing the phase setting in steps of 0500, ie 1000, 1500,
2000, 2500, 3000 etc, until the null point is located.
Lets say for example as we increased the setting there is a
clear reduction in signal as we change from 2500 to 3000,
then from 3000 to 350Q the signal starts to increase again.
This indicates that the null point is between 2500 and 3500.
7) Now reduce phase setting in steps of hundreds ie
3500, 3400, 3300, 3200, etc. the product signal indicated on
the bargraph display should now reduce in amplitude.
Decrease the phase setting in steps of hundreds until the
product effect signal is reduced to a minimum and then just
starts to increase again.
8) At this stage the product effect signal indicated on
the bar graph display should be quite small. To obtain
a more precise phase setting increase the sensitivity setting
to give a larger signal indication on the bar
graph display.
9) Now use the ’tenth digit’ and increase the setting, ie.
3010, 3020, 303Q, 3040, 3050, etc. until the product effect
signal is reduced to a minimum and then just starts to
increase again. Using the tenths digit adjust the phase
setting up and down until minimum signal ie. the null point is
found.
10) Although not always necessary an even more
precise null point will ( be found by now using the ’units
digit” in a similar manner to the tenths digit as described in
9). Using the units digit adjust the
phase setting up and down until minimum signal ie. the
null point is found.
11) The phase discriminator is now aligned to the
product signal, next adjust the sensitivity so that the product
signal gives a maximum signal of 2 to 3 green bars on the
bar graph display.
12) Check the susceptibility of the detector to vibration
if unacceptable reduce the sensitivity until acceptable.
13) Press the ’Enter’ key to store the new settings in
memory.
14) Test the sensitivity of the detector by passing metal
samples through the aperture of the detector (preferably on
or in the product) and note the results.
Minimising Product Effect Signal By Using The
Automatic Setup Facility
Using the auto-setup feature the system will automatically
setup the phase and sensitivity to a product passed through
the detector.
The product will need to be passed through the detector at
least two times during auto-setup and at worst (under large
product signal applications) up to five times.
The system cannot be used to setup automatically on a
continually running product line.
The auto-setup will work successfully with any packaged or
loose product which exhibits a product signal.
For example minimum product effect signal may have
occurred at 3100 and starts to increase again at 3000.
For product effect applications where the product flow is
continuous, such as that found on pipe line systems, manual
phase adjustment must be used. See ’Minimising Product
Effect Signal By Manually Adjusting The Phase
Discriminator’
1) Ensure no product is passing through the detector.
2) Select a sample product which will create a worst case
product effect condition.
3) Enter access code.
4) 4) Select lowest available product number (01 to 20).
5) Select phase.
6) Select automatic – from this point the auto-setup routine
will guide you through each step. Simply follow the
displayed instructions.