Tecnetics Industries Tecweigh 20, Operation Manual

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Check the label on the load cells to see if they are rated at 165 pounds (75 KG). If it is found that
the scale is not using 165 pound load cells, a calibration weight must be provided by the user,
and it’s weight entered in Parameter 5, Cal Wt.
AN AUTO ZERO MUST BE PERFORMED BEFORE AN AUTO SPAN! Make sure Parameter
5, Cal Wt, and Parameter 6, Cal Chain, are set to zero before spanning. Press and hold the AUTO
SPAN button for five seconds. The MODE WINDOW should read, "hold to span", while it is
being held. Release the button after the "hold to span" message disappears. The Auto Span cycle
is now complete.
The HY15 scale is now spanned based on 330lbs (150Kg) of total load cell capacity with 2mv/v
sensitivity. A live material test is now required to attain greater scale accuracy.
7.03.3 Material (Pre/Post) Test
To attain a more precise scale measurement, a material (or pre/post) test must be performed as
follows:
Make sure the calibration weight is raised. While in RUN Mode, press and hold the RESET key
for five seconds to clear the TOTAL display. Weigh and record an empty truck or container on a
certified scale and then run a load of material into it using the conveyor. Try to run at a typical
running RATE and do not perform this test in the rain as the water weight will add to the
material weight. The total load size should be about 10% of the normal running RATE. Example:
normal RATE = 450 TPH, test load = 45 tons.
Now weigh the full truck or container and subtract the empty container weight leaving only the
material weight. In Program Mode go to the P/P Wt Parameter (Section 6.02.9) and enter the test
material weight. When Program Mode is exited, the WP20 will automatically compare the
material test total to the total that it calculated and then modify the ASC Parameter (Section
6.02.55) accordingly. P/P Wt is automatically set to zero after the test is done.
The calculation is:
(Post) Actual Weight/(Pre) WP20 Scale Weight x ASC = New ASC.
If, after the material test, it is shown that the WP20 displayed RATE is not exactly correct,
manually adjust the ASC Parameter up or down to compensate. Also, if an alternate method of
calibration such as a calibration chain is being used, simply adjust the ASC parameter until the
displayed RATE is correct.
Now that the system has been fully calibrated, it is important to save all the acquired information
to the non-volatile RAM in the microprocessor. To do this, simply go to the Params Parameter
(Section 6.02.60), select STORE NOW, and then exit the Parameter Table. Upon exiting, the
Mode window will display “PARAMS SAVED”. Every time a Parameter is changed or the scale
is re-AUTO ZEROed, this same procedure must be done again to save a fresh copy of the
Parameter Table and calibration information.
7.04 Running the System
Now the system is ready to run. With the calibration weight(s) up, the RATE should be zero.
Reset the TOTAL display by pressing and holding the RESET key for five seconds. Begin
running material on the belt. The RATE should increase and the TOTAL should begin to
increment. Press the FUNCTION key momentarily to toggle between the RATE units of measure
and the present belt SPEED. Press and hold the STOP COUNT button to hold the present
TOTAL then release it. Turn the belt off and the message ZERO BELT SPEED should be