Kobold VKG, Руководство по эксплуатации

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VKG
Page 4 VKG K09/0322
Ferritic particles that deposit on the float body (with internal magnet) may also lead
to a similar effect.
The instruments are provided as follows:
Flow measurement
The actual flow may be read locally off the instrument. The top of the float indicates
directly the flow rate in litres per minute on the scale.
Limit Value Contacts (only for model VKG- 2.. and VKG-3..)
For the monitoring of the flow rate, the instruments may be fitted with one or two
adjustable limit value contacts.
Standard design:
Normally open reed contacts (with increasing flow)
Special design: Changeover reed contacts
The contact is adjustable over the full measuring range.
Standard Material Combinations
Material: Brass Material: Stainless Steel
Outer casing Aluminium, anodised Aluminium, anodised
Spring St. Steel 301 St. Steel 301
Orifice St. Steel 301 / brass St. Steel 301
Magnet Ceramic oxide Ceramic oxide
Connections Brass St. Steel 304
Float Brass St. Steel 304
Measuring tube Borosilicate Borosilicate
O-rings NBR FPM
T
max.
100 °C 100 °C
P
max.
12 bar 12 bar
5. Operating Principle
A float with sharp edged orifice apertures is located within
a cylindrical glass measuring tube. When a flow occurs,
the medium lifts the float against a spring which exerts a
force downwards on the float. Each position of the float
corresponds to a particular flow throughput, which may be
read off the scale marked on the glass measuring tube.
Permanent magnets are mounted on the float which
activates reed switches positioned outside of the flow
throughput. The activation of the contacts is carried out by
means of magnetic field, i.e.: the contact is hermetically
separated from the flowing medium.