Multi Station
Vicat Test Apparatus
37
5.2.4 Determining the zero levels of the samples
Figure 39: zero levels
Zero level is defined as the Z-coordinate at which the needle contacts the surface of the glass plate, which
is located in the base. The gradient of the plane in X-direction and Y- direction is determined for each sam-
ple separately.
Xo
– zero-point coordinate X-axis
Yo
– zero-point coordinate Y-axis
Zo
– zero-point coordinate Z-axis
The inclination of each glass plate with respect to the zero point coordinates of the machine is corrected
during the measurement according to the formula below.
Z = Zo + a(X-Xo) + b(Y-Yo)
X = (X-Xo)
Y = (Y-Yo)
Z = (Z-Zo)
a = Z / X
b = Z / Y
Zero levels
to be defined
Please use only glass plates
WITHOUT
Vicat rings
