Specifications; Design And Function - WIKA 70 Manual De Instrucciones

3. Specifications / 4. Design and function

3. Specifications

Specifications
GB
Nominal size in mm
Measuring principle
Filling medium
Capillary entry
Case
Indication accuracy
Scale range
Measuring line
Length of the measuring line
Contact
Load data
Setting range
Standard switch differential
Electrical connection
Ingress protection
per EN 60529 / IEC 529
For further specifications, see WIKA data sheet TV 28.01 or TM 81.01 and the order
documentation.

4. Design and function

4.1 Description
The liquid-filled, closed measuring system consists of a temperature sensor, a capillary
and a Bourdon tube. The volume change as a consequence of the heat applied to the
temperature sensor, and thus the pressure change in the closed system, is transmitted
through the capillary to the Bourdon tube and then indicated on the dial by the angular
deflection of the pointer shaft.
Temperature measuring instruments with micro switch (temperature controllers)
The switching disc (cam disc) connected to the pointer shaft actuates the switching
operation on the micro switch when the switch point is reached.
8
with micro switch
100
Bourdon tube system
Xylol, silicone oil or syltherm
lower mount or back mount
Stainless steel
Class 2
-100 ... +400 °C
Ø 2 mm, stainless steel 1.4571
Max. 10 m
max. 2 micro switches (adjustable/fixed)
5 A, AC 48 V
The instruments do not provide for incorporated overcurrent
protectors. In order to prevent the contacts from welding through
overload, suitable protection systems must be implemented by
the operator.
from 10 % to 90 % of the full scale value
Fixed, factory set to customer specification
< 2 % of measuring range
via cable terminal box
IP 44
WIKA operating instructions expansion thermometer, model 70
without micro switch
63, 100, 160
Xylol or silicone oil
IP 65