Figure A-2. Equipment setup for normal observations.

*TB 43-177

e. Alternately move the leads and make the

measurements as required to obtain observations four

NOTE

through eight to complete the remaining five

The position of the potentiometer

observations of this series.

EMF-REVERSAL switch is governed

Connect equipment as shown in figure A-3 and

by the actual difference between the

measure the difference between cell A of the reference

cell EMFs. When the switch is the "+"

or working group and cell 3 transport standard. Enter the

position, the sign for the observation

observed value, with proper sign, in observation block

is positive (+), when in the "-"

number 9 of the next line (this is the value of cell A-

position the sign is negative (-).

(minus) cell 3). Note that the positive EMF lead of the

Figures A-2 and A-3 reflect typical

potentiometer is now connected to the reference or

switch positions for observations

working group and the negative lead to the transport

when the temperature of the

standard.

transport standard is significantly

g. Alternate move the leads and make the

lower than that of the reference or

measurements as required to obtain observations

working group.

number 10 through 16 to complete the remaining seven

measurements of this series.

A-3