734A Voltage Reference & DC Voltage Standard





The 734A is the only standard of its type offering complete mechanical and electrical independence of each of its four standards.

Small, portable, and rugged

Each standard is small, light and rugged, ideal for shipment. The long 72-hour battery life allows the 732B to be shipped over long distances under power. An optional external battery and charger extends battery life still further, to more than 130 hours.

The 732B can stand up to a lot of abuse. The inputs can be shorted indefinitely and are protected up to 1100V dc, 25 mA, without damaging the cell or affecting its output.


The 732B is based on the proven technology of the 732A, the first standards lab quality electronic reference to gain acceptance as a replacement for saturated standard cells. Originally designed for internal transfers of the Fluke Calibration corporate volt to the production floor, thousands are now in service world-wide in a variety of applications — from maintaining an institutional reference to transferring values from national labs or privately-operated 10V Josephson Arrays.


Stability for each output is ±2 ppm per year (10V) and ±0.8 ppm per month (1.018V). Each 10V output can drive up to 12 mA of current to simplify use with instrumentation – like the 5700A – with low output impedance.

With the 734A, it is remarkably easy to establish a fractional part-per-million voltage reference in your laboratory. Over time, with frequent intercomparisons of the four cells, and regular calibrations of one or more cells, you can reduce the uncertainty of your 734A by a factor of 3 or more.

Support for artifact calibration

Combined with the 742A-1 and 742A-10k Resistance Standards, a single 732B makes a tough and compact artifact calibration support package for instruments like the 5700A/5720A Calibrators from Fluke Calibration or the 3458A Multimeter from Hewlett-Packard.


The simple way to maintain and disseminate your volt

The 732B is a direct voltage standard with 10V and 1.018V outputs. The 734A is a direct voltage reference standard that consists of four 732Bs that are mechanically and electrically isolated, housed in a rack-mountable enclosure.

The 734A is designed to be a primary voltage standard for primary and secondary calibration and standard laboratories. Because it is made up of four independent standards, intercomparisons of the standards and statistical methods can be used to reduce the uncertainty of the reference significantly over time.

Because each 732B is independent, it can be removed from the 734A and used as a portable standard to transfer a value from the primary 734A reference to remote service or production locations for traceability, without disturbing the primary reference.

The 734A is the only standard of its type that meets the design requirements of Technical Note NBS 1239, published by the U.S. National Institute of Standards and Technology in 1987.




10V 30 Day Specification : ± 0.3 ppm
1 Year Specification : ± 1.2 ppm
1.018V 30 Day Specification : ± 0.8 ppm
1 Year Specification : n/a
General Specifications
Temperature 15°C to 35°C, operating; -51°C to 71°C, non-operating (with internal battery pack switched off)
Relative Humidity <95% to 30°C, <75% to 35°C, non-condensing
Altitude <3049m (10,000 ft) operating, <12,195m (40,000 ft) non-operating
Vibration Per MIL-T-28800; Type III, Class 5, Style E
Safety                 Designed to IEC 348, 2nd edition; 1978 and ANSI/ISA-S82; and UL1244, 2nd edition 1980, CSA C22.2 No 231, and IEC 1010
Calibration Documentation Reports of Calibration are optional
Size 734A DC Reference Standard : 17.8 cm H x 43.2 cm W x 50.3 cm D (7 in H x 17 in W x 19.8 in D) (with handles)
732B DC Standard :   13.4 cm H x 9.8 cm W x 40.6 cm D (5.28 in H x 3.86 in W x 15.98 in D)
732B-7001 External Battery and Charger  : 13.4 cm H x 9.8 cm W x 40.6 cm D (5.28 in H x 3.86 in W x 15.98 in D)
Weight                               734A DC Reference Standard  :29 kg (65 lbs.)
732B DC Standard :5.91 kg (13 lbs.)
732B – 7001 External Battery and Charger  :5.45 kg (12 lbs.)
Power, battery life 732B DC Standard : 100V, 120V, 220V, 240V ac ± 10%; 50 Hz to 60 Hz; 66W max. Internal 12V lead acid, gelled electrolyte battery operates for 70 hours at 23°C when fully charged. Trickle-charged continually when external ac power is applied.
732B – 7001 External Battery and Charger : 100V, 120V, 220V, 240V ac ± 10%; 50 Hz to 60 Hz; 66W max. Internal 12V lead acid, gelled electrolyte battery operates for 70 hours at 23°C when fully charged. Trickle-charged continually when external ac power is applied.



Models and Accessories

Model Name Description
734A Reference Standard. Includes four 732Bs in a rack-width enclosure. Calibration of each 732B output optional. See Direct Voltage Maintenance Program.

Accessories common to all models :

Accessory Description
5440A-7002 Low Thermal Test Leads
5440A-7003 Low Thermal Copper EMF Plug-In Cables, Spade Connectors
732B-7001 External Battery and Charger
732B-7002 Transit Case. Holds one or two 732Bs or one 732B and one 732B-7001 External Battery and Charger
734A-7001 Enclosure. Holds up to four 732Bs.
Y734 Rack-Mount Kit for 734A or 734A-7001



Knowledge and Information

Product Manuals
application/pdf icon 732B/734A Instruction Manual (1.39 MB)
application/pdf icon 732B/734A Instruction Manual Supplement (374.25 KB)
application/pdf icon 732B/734A Operators Information (935.27 KB)
application/pdf icon 734A Statement of Memory Volatility (16.81 KB)
application/pdf icon 732B-100I and 732B-000I Instruction Sheet (8.43 KB)
Application Notes
application/pdf icon Fractional PPM Traceability Using Your Fluke 734A/732B (2.14 MB)
Data Sheets
application/pdf icon 734A DC Reference Standard Data Sheet (773.42 KB)