Monroe Electronics Resistivity Meter - Surface - model 262A User Manual
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4. Touch (and hold) the tip portion of the lead to the left rail. The "10
4
" LED should light.
No change in status indicates that either the wrong rail was touched or the lead is
broken.
NOTE: It is normal for the indicator LED's to shift one or two decades as the tip of the
lead is being moved in the vicinity of the sensing rail.
5. Shut the power off and remove the grounding lead from the jack.
OPERATION (Surface resistivity mode):
The function switch must be in the OHMS/SQUARE position and the grounding lead must
be removed for surface resistivity tests.
Material samples to be tested must be able to be completely covered by both contact rails
and must be flat in order for the elastomeric contacts to make a complete connection
along their lengths.
NOTE: Sample specimens narrower than five inches may be tested with a corresponding
degradation in accuracy. For example: a 2 ½ inch wide sample whose surface resistivity
is actually 10
10
ohms per square will be interpreted as 2 x 10
10
ohms per square and will
still be indicated as a static dissipative material -- adequate for many purposes. A ½ inch
wide sample will produce a high reading of one full decade.
Sheet materials should be backed with a flat piece of clean plexiglas (or other good
insulator) whose dimensions are greater than the area covered by the contact rails. The
same (type of) backing material should be used for all testing of materials where results
have to correlate.
After conditioning of sample material (if any) place Model 262A-1 on the selected area of
the sample and apply power. Following the prescribed electrification period, note the
reading and shut off power then continue this procedure with subsequent samples.
OPERATION (Resistance to ground mode):
The function switch must be in the OHMS position and the grounding lead must be
connected between the GND jack on the instrument panel and Hard Ground (utility
ground, system ground, vehicle ground, earth ground, etc. -- the designated reference).
Place Model 262A-1 on the selected area of the mat or other surface to be evaluated.
Apply power and take reading.
HOW TO OBTAIN ASTM STANDARD:
Monroe Electronics does not supply copies of ASTM standards.