Fluke 3458/HFL, 8508A specifications Last Acal

8508A vs 3458/HFL
Functional & Versatility				Comments
Parameters
High Resistance	Test Voltage or Full Scale		Test Voltage or Full Scale	Reduces errors when performing high
Measurement (compliance				resistance measurement (feature available
	stimulus = 200V		stimulus @ 1.2GΩ = 5V
voltage)				8508A - 20MΩ to 20GΩ range only)
Tru-Ohms or Offset				Current reversal reduces errors caused by
	Current Reversal	Switched Current		thermal emfs as does switched current but
Compensated Resistance
				reversal technique has the added benefit of
technique.
				reducing errors due to self heating
Store RTD temperature	Supports a wide variety of PRT &			PRT calibration coefficients are stored (max
			Not Available	100 probes) within the 8508As internal
coefficients	SPRT sensors
				memory.
				8508A - Precision without the need for
ACAL	Not Required		Required every 24hrs or ±1º C	internal drift corrections. ACAL will overwrite
			of last ACAL	last stored value and cannot be retrieved.
				This might be important for users that
				require ‘as found data’.
				Auto-zero must be enabled on 3458A/HFL if
Auto-zero (A-zero)	Range zero is enabled by operator		A-zero should be enabled to	environment exceeds ±1°C of last Input
				zero. Zero/nulling meters before
			maintain specification	measurement is accepted metrology
				practice.
				8508A is less intrusive when compared with
				conventional meters when measuring low
				magnitude current sources. The 8508A
Low impedance low Current	Yes		No	input impedance on the 200uA range is 60
measurement technology				Ohm. This low impedance mimics
				technology normally found in Electrometers
				and picoampmeters. This compares with 5k
				– 10k Ohm on other DMMs.
ACV measurement			Analog, Synchronous and	Digitize sub sampled techniques are useful
	Analog True rms			when measuring low frequency <1Hz input
technique			Random sampled ac
				signals.