Fluke 35040 - Theory of Operation; B.5 Theory of Operation

Appendix
Theory of Operation
B
B-11
B.5 Theory Of Operation
Basic Operating Equations
Quantity Description Units Comments
Q
Timed
Timed Charge C The electrical charge delivered during the timer
interval.
Q
Timed_Predicted
Predicted
Timed Charge
C The total amount of timed charge that should be
accumulated at the completion of the timer
interval, based on the observed delivery rate.
Leakage Measurements
Leakage measurements (Q
Offset,
I
Leakage
and T
Offset
) are only applicable when automatic leakage
compensation is enabled.
Timed Charge and Dose
This measurement accumulates charge only while the elapsed time is less than or equal to the timer
interval setting. The displayed value is held following the completion of the timer interval.
()()
[s] [s] [A] [C] [C] 12Leakage12Timed TTIQQQ
−
×−−=
ADCFICCFQDose TimedTimed ××= [Units/C] [C]
Q
1
represents the next sample of charge at time T
1
following the activation of the timer. Q
2
corresponds to
the interpolated charge at time T
2
, where T
2
is an integral number of seconds that is restricted to times
within the range: T
1
< T
2
≤ (T
1
+ Timer Interval Setting).
Predicted Timed Charge and Dose
This measurement extrapolates the timed charge (Q
Timed
) at the elapsed time (T
Elapsed
) that should be
accumulated at completion of the timer interval (i.e., TimerIntervalSetting) based on the rate of charge
delivery.
[s]
[s]
[C]
valSettingTimerInter
T
Q
Q
Elapsed
Timed
ictedTimed_Pred
×=
ADCFICCFQDose ictedTimed_PredictedTimed_Pred
×
×= [Units/C] [C]
At the conclusion of the timer interval (i.e., T
Elapsed
equals the TimerIntervalSetting), the predicted timed
charge and dose are equal to the predicted timed charge and dose, respectively.