General description
The KSR flow switches are used to display and monitor the flow of liquid
and gaseous media e.g. in cooling systems and cooling circuits on welding
machinery, laser and cathode ray equipment, dosing systems, pumps, compressors,
hydraulic systems, high pressure plant and many more.
Measuring principle
The KSR flow switches operate on the suspended body measurement principle.
A suspended body is guided in a cylindrical slotted nozzle. A reed contact
is fitted outside the flow circuit. The reed contact is cast into a smoothly
adjustable housing (switch housing) and thus protected from external influences.
The medium, as it flows in, moves the suspended body in the direction
of flow. When the suspended body with its integral magnets reaches the
position of the reed switch, this will be closed. If the flow rate increases,
for the suspended body will move further in the direction of flow, at
maximum until it reaches a stop. This stop prevents the suspended body
from travelling past the switching range of the reed switch (bistable
characteristics).
Switching ranges
All KSR flow switches are fitted ex-works with a normally open contact.
The switch point can be smoothly adjusted within the switching range.
The actual flow rate, corresponding to the velocity of flow present, can
be much larger than the maximum scale value (typically twice as large).
Position dependent
The KSR flow switches DWG, DWM and DWM/A must be fitted vertically with
the direction of flow from bottom to top. For all other types installed
position is optional, but care must be taken to ensure the correct direction
of flow when installing.
Switching hysteresis
This is how the distance of the suspended body between switch-on and switch-off
flow rate is described. The shorter this switching distance, the lower
the switching hysteresis, and the more precise the operation of the unit.
By selecting magnets and reed switches with a small difference between
response and drop-out excitation (close differential) the switching hysteresis
is successfully kept low. Low switching hysteresis is always an advantage
where accuracy is required.
Display
A local display is possible. On types with a sight glass the upper face
of the suspended body is the read-off edge and indicates the flow on the
scale etched into the sight glass. Models with a pointer scale can be
read off corresponding to the scale. Please ensure that the particular
scale is a matched to a particular medium.
Technical advantages High switching precision
High functional reliability
Low switching hysteresis
Stepless switch point adjustment
Large switching range
Robust design
Viscosity compensated types are available
