Accuracy

Question 1

What is a systematic (bias) error

Answer 1

An error that effects every measurement by the same amount. It can also be described as the difference between the ideal value and the average of the measured values.

Question 2

What are the two types of systematic errors?

Answer 2

1) Variable bias error: these errors occur due to wear and tear of materials in a certain system over time. i.e. progressive wear of an orifice plate edge overtime will cause a systematic error in DP measurement

2) Constant bias error: these errors occur from unknown bias error in a reference standard

Question 3

______ errors can be calibrated out but _______ errors will always have drift

Answer 3

Systematic (bias), precision (random)

Question 4

What is a precision error?

Answer 4

An error that is represented as a deviation around the average.

Question 5

How much more accurate should the calibration standard be than the instrument being calibrated?

Answer 5

10 times

Question 6

When is the reference instrument rating not taken into account?

Answer 6

When it’s more than 10 times accurate

Question 7

When is the reference instrument rating taken into account?

Answer 7

When the reference instrument is 4-10 times more accurate.

Note: less than 4 times more accurate references are not accepted