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Milltronics SF 500 – INSTRUCTION MANUAL
7ML19985CN01
mmmm
m
Recalibr
at
ion
Recalibration
Material Tests
Perform material tests to verify the accuracy of the span calibration and compensate for
material flow. If the material tests indicate a repeatable deviation exists, a manual span
adjust (P019) is then performed. This procedure automatically alters the span calibration
and adjusts the test rate (P017) value, yielding more accurate span recalibrations.
If the span adjust value is within the accuracy requirements of the weighing system, the
material test was successful. Resume normal operation.
If the span adjust value is not acceptable, repeat the material test to verify repeatability. If
the result of the second material test differs considerably, consult Siemens Milltronics or
any of its agents.
If the span adjust values are significant and repeatable, perform a manual span adjust.
There are two methods of executing the manual span adjust:
% Change
and
Material
Test
•
% Change
: based on the material test, the difference between the actual weight of
material and the weight reported by the SF 500 is calculated and entered into P019
as % change.
•
Material Test:
based on material test, the actual weight of material is entered into
P019.
The method of execution is a matter of preference, and yields the same result.
% Change
To run a % Change material test:
1.
Stop material flow.
2.
Perform a zero calibration.
3.
Put the SF 500 into RUN mode
4.
Record the SF 500 total as the start value _ _ _ _ _ _
(e.g. 17567.0)
5.
Run material at a minimum of 50% of design rate for a minimum of 5 minutes.
6.
Stop the material feed.
7.
Record the SF 500 total as the stop value _ _ _ _ _ _ (e.g. 17995.5)
Subtract the start value from the stop value to determine the SF 500 total
8.
Determine the weight of the material sample.
SF 500 total = _ _ _ _ _ _(e.g. 428.5 kg)
material sample weight = _ _ _ _ _ _ (423.0 kg)
Note:
Test weights are NOT used during material tests.