Safety; Packaging List; Introduction; Measurement Method - Selecta ST-2020-L Manual De Instrucciones

MANUAL DE INSTRUCCIONES CODIGO 80239 REV C
(1) motor
(4) spring
(3) sample
(2) spindle
Fig. 3.1
J
.P. SELECTA s.a.u.
Sep2016

1. Safety

Please bear in mind the safety information of the liquids used.
See also chapter 9.

2. Packaging List

- Briefcase (Two cases on the 1001617)
- Main unit
- Rack shaft
- Support feet.
- Spindle Model «L»
- Spindle binder
- Spindle protector
- Spanner
- Power Inlet: 110-230 VAC
- Temperature probe
- Cable RS-232

3. Introduction

The rotational viscosimeter is used for measuring dynamic viscosity. This feature ex-
presses the substances resistance to distortion when a cutting effort is being applied.
This is a highly dependent property of the measurement temperature.
As an example, we have the chocolate: in a small temperature margin, its almost
infinite value viscosity (at about 10ºC is completely solid) at a very low value (at
about 60ºC is completely liquid).
Viscosity is measured by establishing the necessary force (cutting or shear effort
(N/m2) to move the particles of material g with a particular distortion speed (speed
gradient, (S-1)). The viscosity (h) is obtained as a result of the ratio between the
cutting effort and the speed gradient.
The measurement unit is the Poise (P), although in practice we use either its hundredth
part (cP) or mPa.s in the International System.
The relationship with static viscosity is as follows:
Dynamic V = Static V x density
Other concepts to bear in mind on dynamic viscosity measurement are:
Thixotropy: variation of viscosity with time. For instance: «Quick dry» glues and paints.
Newtonian / Non-Newtonian: constant viscosity in time / varying viscosity

3.1 Measurement method

Figure 3.1 offers a schematic of the measurement system.
The system is made up of a motor (1) which makes the spindle (2) turn, immersed
in the sample (3), and joined by a spring (4).
Due to the resistance the sample offers to the spindle, its turn is retarded with regard
to the motor.
Rotational viscosimeters use this «retard» to calculate dynamic viscosity.
This «retard» increases the spindle size and the angular speed (rpm).
Ctra. NII Km 585.1 Abrera 08630 (Barcelona) España
e-mail: [email protected] - website: http://www.jpselecta.es
(Sujetas a modificaciones sin previo aviso)
# 1; # 2; # 3, # 4
(Placed on the same case)
Model «R» R2; R3; R4; R5; R6; R7
(Placed on a separate case)
Outlet: 15V 1.5A
Pag.: 12
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