Thermo Scientific HAAKE RotoVisco 1 Instruction Manual page 120

Sensor Systems
Plate/plate measuring errors
Significant measuring errors can result when using plate/
plate sensor systems if ...
 the correct gap between the plates is not observed,
 filling is not carried out correctly.
Both errors can be estimated quantitatively:
1. Plate/plate gap error
If the desired gap h which is set at the rheometer is not
observed, the following measuring uncertainty results:
Measuring uncertainty = h / h
2. Plate/plate reduced effective radius error
If a plate/plate sensor system is insufficiently filled or the gap
empties itself during a measurement, significant measure-
ment errors can result. This condition of insufficient filling can
be referred to as a reduced effective radius error and is char-
acterized by a reduction in the effective radius.
R
R
h
eff
R = R -- reduced effective radius x
eff plate
Viscosity measuring
η
korrekt
uncertainty =
118
R = plate radius
h = gap
R
= effective radius
eff
x
R
eff
− η
Fehler
= 1 −
η
korrekt
h + h
reduced effective
radius
4
R
4
(R − x)