Conair WSB - Manual (Page 86)

LOAD CELL plus WEIGH BIN TEST
to verify correct operation
This test is to help you determine if the load cells are working
correctly, and if the weigh bin and weigh bin hanger are moving freely
and registering weight correctly.
Have a pad and pencil ready to write down the weight readings that
appear on the display, both before and after each dispense. If you
prefer, you can use a printer to record all test data. Have the
printer flag (*54) set to ON.
Be in the PROGRAM mode. (*22222).
1. Start with an empty weigh bin.
2. Dispense a very small amount, using the TIMED DISPENSE function:
Record the weight display.
Press: TIME, NAT, 040
Wait for dispense then record the new weight.
Wait for test to finish, about 10 seconds. At the end of this test
the bin will automatically empty.
3. Now, manually add enough pellets to bring bin weight up to the
approximate full batch weight. Do this by pressing on the small
air solenoid operator pin for NATURAL. Drop in enough pellets to
be close to a normal full batch weight, like 2000 or 4000 grams.
Exact weight does not matter. We just want to place the
approximate full batch weight on the load cells.
4. Repeat step 2, recording the weight readings.
5. Do this entire test 3 more times.
From the weight readings, calculate the weight of each dispense
from each test.
RESULTS TO EXPECT:
In each test, the first timed dispense, when the bin is empty, should
be very close or equal to the second dispense, when the bin is full.
Results from all 4 tests should be very similar.
If the second dispense is always less then the first, the load cells
are suspect. The enclosures may be full of pellets. Weigh bin
interference is also possible. If all dispenses vary widely with no
pattern, this is most likely caused by weigh bin interference. Weigh
Bin interference is usually visible with close inspection.
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