Scope

*TB 43-177

Scope

Run. A sequential group of observations in a

test procedure or measurement design.

a. This bulletin applies to all

CRC's

that

g. Test. A process by which data is accumulated

participate in the US Army Volt Program.

to serve as a basis for assessing the degree that a

system meets, exceeds, or fails to meet the technical or

b. This bulletin applies specifically to the following

operational specifications assigned to the system.

saturated cell models:

h. Measurement. The process of comparing an

(1) Standard

cells

with

temperature

Enclosure, Eppley Laboratories, Inc., Model 106-4 (APN

instrument or test system to an accepted standard.

7909096).

Measurement Design. A design selected to

(2) Saturated standard cell Enclosure,

intercompare a group of standards.

Designs are

Guildline Instruments, Inc., Model 9154 ( ) (all models).

selected to provide maximum information with a

minimum number of observations.

3. Definitions. In addition to the definitions in AR 750-

25 and AR 310-25, the Following definitions apply:

Thermal EMF. The thermoelectric potential

generated by leads and/or binding posts of the reference

a. Saturated Standard Cell. A chemical cell in

device when connected into a circuit with pure copper

which the electrolyte is kept ;saturated at all times by the

connections.

presence of an excess of solid crystals.

k. Calibration and Repair Center (CRC). A

b. Transport Standard. A group of standard

functional organization established for the purpose of

cells used to compare the unit of voltage maintained at

providing single source Calibration and Repair Service

one location to that maintained at another location. A

(C&RS) for general purpose and selected special

transport standard can either be used to calibrate a

purpose TMDE.

reference standard or to disseminate the colt from the

reference standard to other lower level standards.

4. General. Figure 1 indicates an ideal flow of the volt

within the calibration system. It indicates an ideal

c. Reference Group. A designated group of

traceability chain from the "Legal Volt" at the National

cells used only for maintaining the volt in a calibration

Bureau of Standards (NBS) to the lowest level of the

facility. This group is lot normally used in performing

Army Calibration System. As the chart indicates, the US

routine calibrations.

Army Volt is linked to the US Legal Volt at NBS with

procedures of the NBS Volt Transfer Program and

transportable standard cell enclosures. The CRC Volt is

d. Working Group. A designated group of cells

linked to the US Army Volt at the APSL with procedures

which may be used as a standard for performing routine

of this technical bulletin and transportable standard cell

calibrations in a calibration facility.

enclosures supplied and controlled by the APSL. Local

surveillance of cells in the reference and working groups

e. Observation. A noted occurrence involving a

at the CRC will be performed in accordance with

measurement with a standard or test system. An

procedures of appendix B.

observation is the simplest piece of information (data)

that has independent significance in a calibration.