Eriez E-Z TEC IV, Инструкции по установке, эксплуатации и обслуживанию

Страница: 43 / 100

®
43
4. As the product enters the aperture, note the
INITIAL DEFLECTION of the Monitor (right or
left) and record it along with the Phase control
setting.
5. Change the Phase control to a setting of 10
greater than the previous value and pass the
product through the aperture again. Note the
initial deflection direction of the Monitor and
record it.
6. Repeat step 5 until Monitor response to the
product changes to the opposite direction.
When this happens the product phase out point
lies somewhere between the last two settings.
For example, if the Monitor initial response was
to the left with a Phase setting of 40.0 and to
the right with a Phase setting of 50.0, the phase
out point lies somewhere between 40.0 and
50.0.
NOTE: It will be necessary to wait briefly after
each adjustment of the Phase switch before
passing the product through the gap.
7. Adjust the Phase switch to the midpoint of the
last two settings (i.e., 45.0 in the example).
8. Pass the product through the aperture and note
the Monitor initial deflection direction and
record it.
9. Repeat step 8 while varying the “1’s” digit of
the Phase switch. Continue until the minimum
Monitor deflection is obtained.
10. Repeat steps 8 and 9 with the tenths digit.
11. The phase adjustment is now complete.
12. Increase the SENSITIVITY control to a point
where the product can be passed through the
gap without being detected but with the Sensi-
tivity control as high as possible.
NOTE: The Sensitivity of the detector is determined
by passing the product with a series of test spheres
through the aperture after the above adjustments
have been made. The Sensitivity is expressed as
the diameter of the smallest sphere that can be
detected reliably.
REJECT ADJUSTMENT ANALOG
UNITS
Each E-Z Tec Version IV and V analog metal detector
has two separate reject timers that run in parallel:
DIRECT REJECT and TIMED REJECT. The output
signals of these two timers appear at the terminals
labeled “DIRECT RELAY” and “TIMED RELAY”,
respectively, on the Power Supply Output Board.
Adjustments to the reject timing are made using the
switches and jumpers on the Power Supply Output
Board (refer to Switch Charts A and B on page 23).
DIRECT REJECT
Direct Reject output is usually used in applications
which are very fast and cannot tolerate a delay in
the reject command. An example is a vertical fall
application.
Direct Reject output begins at the instant metal is
detected and continues for the length of time metal
is detected plus the duration of the DIRECT
REJECT TIME, which may range from
approximately 0.1 to approximately 1 second. The
Direct Reject Time is adjusted via the DIRECT
REJECT POTENTIOMETER, located directly under
the “CLOCK” label on the Power Supply Control
Panel. (See Figure 7. Also, note that on most E-Z
Tec IV or V analog units this potentiometer is blue.)
It is worth emphasizing that the Direct Reject
potentiometer affects only the duration of the Direct
Reject signal, and not the initiation of the signal. As
stated above, the Direct Reject output signal is initiated
essentially instantaneously upon detection of metal.
Consequently, in applications where the product is
widely spaced as it passes through the metal detector
(specifically, where individual product items are more
than about 1 second apart), appropriate adjustment
of the Direct Reject time can be accomplished simply
by setting the Direct Reject Pot at or near its maximum
setting. The reject signal will then appear
instantaneously upon detection of metal and will
remain for about 1 second, at which time it will return
to its non-detect condition. Since only one product
item will have passed the reject device in that time
period, the contaminated product is certain to be
rejected and no excess product will be lost.
Configuring Analog Metal Detector (cont.)