3M 701 Calibration Procedure - Page 2

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Also for 3M 701: Operator's Manual (8 pages), Operator's Manual (9 pages)

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readings are shown on the top scale of the meter as small dots on

either side of the respective resistance mark on the dial.)

E. Remove the decade box. Using the Keithley 619, verify that the output

is between 93V and 107V in the 100V SURFACE TEST mode.

F. If above specifications can not be obtained proceed to Section 4,

Calibration Procedures

4. CALIBRATION PROCEDURES

A. Place the batteries in the unit. Place the selector switch in the BATTERY

TEST position.

B. Press the TEST button, adjust R10 so that 10.00 V ± .01V appears

between U2 Pin 7 and ground. Release the TEST button.

C. Press the TEST button. Adjust R23 for 100.0V ± .1V between SW 1 Pin 12

and ground. Release the TEST button.

D. Place the selector switch in 100V SURFACE TEST position. Short the

input jacks. Press TEST button. Adjust R21 so that pointer reads full

scale. Release TEST button.

E. Return the selector switch to BATTERY TEST. Press the TEST button.

Adjust R36 so that the pointer lies over 100V mark on BATTERY TEST

scale. (For Issue 1 PC Boards, adjust the value of R8 to align the pointer,

as above. You will be able to find the issue number in the vicinity of the

TEST switch on the PC board.) Release the TEST button.

F. Place the unit in its case. Verify that the unit reads within the tolerance

limits for the following resistances in both the 10V and 100V SURFACE

TEST modes: 100KΩ, 1 MΩ, 10MΩ, 100MΩ, 1GΩ, 10GΩ. (Tolerances for

the 1 MΩ - 10GΩ readings are shown on the top scale of the meter as

small dots on either side of the resistance range. For the 100KΩ range,

estimate ± 2° either side of the 100KΩ mark on the upper scale of the

meter.)

G. Verify that the unit reads properly with a short and then a 100KΩ

resistance across the test leads in the CONTINUITY TEST mode. (NOTE:

for the 100KΩ range, estimate ± 2° either side of the 100KΩ mark on the

continuity scale of the meter.)