Milwaukee Tools Doll MR100ATC Fascicule

Scale Range Resolution 
Parts Per Thousand 0 to 100 0/00 1 0/00 
Specific Gravity 1.000 to 1.070  
Dimensions 7.6 x 1.5 x 1.5" (194 x 38 x 38mm) 
Weight Approx. 8.0 oz. (227g) 

 

 
 
 
 
                    Shadow-line Æ 

 
 
 

 
Operation 
The instrument measures the refractive index of the sample and displays the result in parts 
per thousand ( 0/00 ) and specific gravity. 
 
1. Zero Adjustment 
Put distilled water on the prism; enough to cover the entire prism. Close the cover plate and rotate 
the adjusting screw so that the light/dark boundary line (known as the shadow-line) evens up with 
the zero line. After the zero adjustment, clean the prism with soft cloth.  
 
2. Sample Preparation and Reading 
To take a reading, place a few drops of a sample liquid on the measurement prism. Ensure that 
enough solution is added to the prism in order to cover the entire prism. Close the prism so that 
the liquid spreads across the entire surface of the prism without air bubbles or dry spots (see 
diagrams below). Allow the sample to remain on the prism for approximately 30 seconds. While 
holding the instrument under a light source, look through the eyepiece. The salinity concentration 
is determined by the intersection of the boundary of the light and dark fields (known as the 
shadow-line) on the printed scale. The left side of the scale indicates the specific gravity and the 
right side parts per thousand. If the scale appears out of focus, the eyepiece may be adjusted by 
rotating the knurled portion. The instrument also features an eye guard to prevent stray light from 
entering the eyepiece and causing reflections. It may be necessary to adjust the position of the 
light source to maximize the contrast of the shadow-line. Under normal conditions, optimal 
contrast is obtained by holding the instrument underneath and perpendicular to a light source. 
(florescent light is not recommended) - Once a reading has been taken, wipe dry with a clean 
cloth (do not wash or rinse) and place the instrument in the supplied plastic case. Store the 
instrument in a safe, dry environment.