The Fisher 21 tensiometer is suitable for educational and industrial control applications.
Application of torsion to raise ring and simultaneous lowering of sample table are done manually.
Parallax errors are eliminated by aligning index needle on lever arm with line on mirror.
Tensiometer is capable of upward and downward measurement of tension.
Dual scale graduated from 0-90 dynes/cm in clockwise & counterclockwise direction.
Direct results, no calculations. Force necessary to separate ring from liquid measured & read directly to +/-0.25 dynes/cm.
Includes certificate of calibration and ring
Semiautomatic Tensiomat performs ASTM D 971-99a (oil-water interfacial tension procedures) and D 1331-89 (methods for measuring surface and interfacial tension of detergents)
Employs du Noüy ring method for direct results with no calculations
Accuracy equals data from capillary-height or drop-weight measurements to within ±0.25%
Measures force necessary to separate platinum-iridium ring from liquid, read directly to ±0.25 dynes/cm
For comparative studies, data is easily convertible to absolute values using graph in supplied instructions
Reversible motor for improved accuracy compared to manual tensiometers