Fluke 8842a instruction manual Measurement Tutorial

			Contents (continued)
	3-50.	The Serial Poll Register	3-27
	3-51.	The SRQ Mask	3-28
	3-52.	INTERFACE MESSAGES	3-29
	3-53.	Address Messages	3-29
	3-54.	Universal Commands	3-29
	3-55.	Addressed Commands	3-30
	3-56.	TALK-ONLY MODE	3-30
	3-57.	REMOTE CALIBRATION	3-31
	3-58.	TIMING CONSIDERATIONS	3-31
	3-59.	IMMEDIATE MODE COMMANDS	3-31
	3-60.	EXAMPLE PROGRAMS	3-32
4	Measurement Tutorial		4-1
	4-1.	INTRODUCTION	4-2
	4-2. DC VOLTAGE MEASUREMENT		4-2
	4-3.	Circuit Loading Error	4-2
	4-4.	Input Bias Current Error	4-3
	4-5.	RESISTANCE MEASUREMENT	4-4
	4-6.	2-Wire Ohms	4-4
	4-7.	Correcting for Test Lead Resistance in 2-Wire Ohms	4-5
	4-8.	4-Wire Ohms	4-5
	4-9.	Applications of the Ohms Functions	4-7
	4-10.	TESTING DIODES	4-7
	4-11.	TESTING ELECTROLYTIC CAPACITORS	4-7
	4-12.	A PRECISION CURRENT SOURCE	4-8
	4-13.	DC CURRENT MEASUREMENT	4-8
	4-14.	REDUCING THERMAL VOLTAGES	4-9
	4-15.	AC VOLTAGE AND CURRENT MEASUREMENT	4-10
	4-16.	True RMS Measurement	4-10
	4-17.	Waveform Comparison	4-10
	4-18.	Crest Factor	4-12
	4-19.	AC-Coupled AC Measurements	4-12
	4-20.	Combined AC and DC Measurements	4-13
	4-21.	Bandwidth	4-13
	4-22.	Zero-Input VAC Error	4-13
	4-23. MAKING ACCURATE MEASUREMENTS ON THE 20 mV
		AND 20Ω RANGES	4-14
	4-24.	MAKING ACCURATE HIGH-RESISTANCE MEASUREMENTS . 4-15
5	Theory of Operation		5-1
	5-1.	INTRODUCTION	5-3
	5-2. OVERALL FUNCTIONAL DESCRIPTION		5-3
	5-3.	DETAILED CIRCUIT DESCRIPTION	5-4
	5-4.	DC SCALING	5-4
	5-5.	VDC Scaling	5-6
	5-6.	VDC Protection	5-7
	5-7.	mA DC Scaling	5-7
	5-8.	Analog Filter	5-7
	5-9.	TRACK/HOLD CIRCUIT	5-8
	5-10.	Track Configuration	5-10
	5-11.	Settling Configuration	5-11
	5-12.	Hold Configuration	5-11
	5-13.	Pre-Charge Configuration	5-11
	5-14.	PRECISION VOLTAGE REFERENCE	5-11

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