CareFusion LTV 1100, Service Manual

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Page E-12 LTV
®
1200, 1150, and 1100 Ventilator Service Manual p/n 18603-001, Rev. J
Tools, Required
LTV
®
Service, Calibration and Testing require instrumentation tools or test equipment with
documented calibrated traceability to NIST standards.
The instrumentation and test equipment must also have sufficient accuracies to attain
industry standard performance levels.
Instrumentation accuracy is typically specified “percent of full scale” or “percent of reading”.
The required minimum accuracy levels are typically the specification tolerance divided by
four (4).
When minimum accuracy levels are not attainable, the specification’s tolerance shall be
“guard-banded” or reduced by the instrumentation’s accuracy to maintain industry standard
performance levels.
The following examples are provided to help illustrate the instrumentation and test
equipment requirements.
Volume measurements
1500 ml
When measuring a volume of 1500 ml with a tolerance of ± 150 ml, the resulting minimum
accuracy level for instrumentation would be 150 ml / 4 = 37.5 ml.
If the instrument accuracy is 2% of reading, at 1500 ml the resulting accuracy is 1500 ml x
2% = 30 ml. The resulting accuracy is less than the minimum accuracy level (37.5 ml) and is
acceptable.
If the instrument accuracy is 2% of full scale and the instrument has a full scale of 2000 ml,
the resulting accuracy is 2000 ml x 2% = 40 ml.
Under these conditions, reduce the tolerance from ± 150 ml by the accuracy of the
instrument (40 ml) for a “guard-banded” tolerance of 1500 ml ± 110 ml = 1390 ml to 1610
ml.
500 ml
When measuring a volume of 500 ml with a tolerance of ± 50 ml, the resulting minimum
accuracy level for instrumentation would be 50 ml / 4 = 12.5 ml.
If the instrument accuracy is 2% of reading, at 500 ml the resulting accuracy is 500 ml x 2%
= 10 ml. The resulting accuracy is less than the minimum accuracy level (12.5 ml) and is
acceptable.
If the instrument accuracy is 2% of full scale and the instrument has a full scale of 1000 ml,
the resulting accuracy is 1000 ml x 2% = 20 ml.
Under these conditions, reduce the tolerance from ± 50 ml by the accuracy of the
instrument (20 ml) for a “guard-banded” tolerance of 500 ml ± 30 ml = 470 ml to 530 ml.
300 ml
When measuring volume of 300 ml with a tolerance of ± 30 ml, the resulting minimum
accuracy level for instrumentation would be 30 ml / 4 = 7.5 ml.
If the instrument accuracy is 2% of reading, at 300 ml the resulting accuracy is 300 ml x 2%
= 6 ml. The resulting accuracy is less than the minimum accuracy level (7.5 ml) and is
acceptable.
If the instrument accuracy is 2% of full scale and the instrument has a full scale of 500 ml,
the resulting accuracy is 500 ml x 2% = 10 ml.
Under these conditions, reduce the tolerance from ± 30 ml by the accuracy of the
instrument (10 ml) for a “guard-banded” tolerance of 300 ml ± 20 ml = 280 ml to 320 ml.