ABB EasyLine EL3060 Series User Manual

108 EL3060 CONTINUOUS GAS ANALYZERS | OI/EL3060-EN REV. A
Control charts
CUSUM control charts
CUSUM control charts enable the precision and drift of the AMS at the zero
point and reference point to be determined separately.
Performance characteristics for determination of the precision
hs hs = 6,90 s
2
AMS
Test value for detection of a decrease in the precision
ks ks = 1,85 s
2
AMS
Constant for the calculation of the interim sum total for the standard
deviation
dt Difference between the current instrument display of the AMS and the reference value (Note
the preceding sign)
sp Interim standardized sum total of the standard deviations of the AMS
st Interim standardized sum total of the standard deviations of the AMS at the point of time t
N(s)t Number of instrument displays since a standard deviation from zero occurred
Performance characteristics for determination of the drift
hx hx = 2,85 s
AMS
Test value for detection of a drift
kx kx = 0,501 s
AMS
Constant for calculation of the interim sum total of the positive and neg-
ative differences and for calculation of the requisite correction of the
AMS
dt Difference between the current instrument display of the AMS and the reference value (Note
the preceding sign)
Sum(pos)p Interim standardized sum total of the positive drift of the AMS
Sum(pos)t Standardized sum total of the positive drift of the AMS at the point of time t
N(pos)t Number of instrument displays since a positive deviation occurred
Sum(neg)p Interim standardized sum total of the negative drift of the AMS
Sum(neg)t Standardized sum total of the negative drift of the AMS at the point of time t
N(neg)t Number of instrument displays since a negative deviation occurred
Test for "decrease of precision"
st smaller than or equal to hs
for both zero point and end point
AMS is operating in the control range, carry out a drift test
st greater than hs
for either zero point or end point
Determine cause of fault, notify manufacturer if instrument is
defective (drift test not necessary)
Drift test
Sum(pos)t smaller than or equal to hx and
Sum(neg)t smaller than or equal to hx
for both zero point and end point
AMS is operating in the control range
Sum(pos)t greater than hx or
Sum(neg)t greater than hx
for either zero point or end point
Measured value is outside the control range ("Out of Con-
trol"), carry out a readjustment of the AMS

ABB EasyLine EL3060 Series Specifications

General

Brand	ABB
Model	EasyLine EL3060 Series
Category	Measuring Instruments
Language	English