Fluke 35040 manual Manual Addenda, Specifications, Charge Measurements, Maximum Error

		General Information	1
		Safety Symbols and Terms
The	CAUTION	heading used in this manual explains hazards that could damage the instrument.

Such damage may invalidate the warranty.

1.5 Manual Addenda

Any improvements or changes concerning the instrument or manual will be explained in an addendum included with the manual. Be sure to note these changes and incorporate them into the manual.

1.6 Specifications

Charge Measurements

Range, Resolution and Repeatability:

Full Scale Range		Display Resolution		Repeatability (±
				counts)
200.00	pC	0.01	pC	5
2.0000	nC	0.0001 nC		1.5
20.000	nC	0.001	nC	2.5
200.00	nC	0.01	nC	1
2.0000	μC	0.0001	μC	1
20.000	μC	0.001	μC	1
200.00	μC	0.01	μC	1
2.0000	mC	0.0001 mC		1
20.000	mC	0.001	mC	1

Measurement Method: Charge flowing into the input is integrated using a capacitive feedback electrometer whose output is measured by means of a 20 bit bipolar A-D converter. A high-speed reset circuit removes the integrated charge on the feedback capacitor each time it reaches a level of 2 nC in either polarity. By monitoring both the number of 2 nC resets and the charge on the feedback capacitor, the total charge flowing into the input is determined.

Factory Calibration: Basic factory charge calibration is performed by injecting -1.90 nC and ± 19.0 nC via a precision standard air capacitor. This method is believed to provide a calibration accuracy of ± 0.05%rdg (± 0.05% of reading) as detailed in the table below:

Factory Calibration Error Source	± (%rdg)
Charge Source Accuracy (Capacitor)	0.01
Charge Source Accuracy (Voltage Change)	0.01
Temperature Effects (21°C – 25°C)	0.02
Other	0.01
Maximum Error	0.05

The field adjustable current and charge scale factors are set to their nominal value of 1.000 during factory recalibration.

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