Festo MS-LFM-...-DN Series, Operating Instructions Manual

Page: 31 / 56

MS
Ū
−LFM−
Ū
−DP/DN/DPI/DN I
Festo MS
Ū
−LFM−
Ū
−DP/DN/DPI/DNI 0611NH English
31
2 Function and application
The filter contamination recognition with display MS
Ū
−LFM−
Ū
−DP/DN/DPI/DNI has
been designed for monitoring the degree of contamination in the fine/micro filter
MS
Ū
−LFM. The degree of contamination is derived from the continuous measure
ment of the differential pressure which increases with rising contamination.
Measurements are carried out using a piezoresistive sensor element with a follow
ing electronic evaluation unit. The measurement result is shown numerically on the
display. Connection to higher−order systems is carried out via a switching output.
The switching point for the filter cartridge replacement is adjustable.
The switching outputs can be configured as nc" and no" contacts. The desired
switching points can be defined as threshold comparator or window comparator.
The product designs MS
Ū
−LFM−
Ū
−DPI/DNI also offer an analogue output which
passes the measured differential pressure on as an electric pressure−proportional
signal.
T erm E xplanation
Differential
pressure Pressure drop in the fine/micro filter MS
Ū
−LFM between the input
and the output. The differential pressure depends on the flow and on
the degree of contamination.
Maximum
pressure 350mbar
Fixed end value for the differential pressure in the unit %". The
value corresponds to 100%. We recommmend that you replace the
filter cartridge when this value is reached.
Basic pressure Medium value of all measured differential pressure values in a
particular time interval. The basic pressure is the starting pressure
for the filter contamination recognition in percent display
(0% contamination corresponds to new filter status).
The basic pressure must be ascertained in order that the filter
contamination reognition can be carried out faultlessly. A new filter
indicates a particular pressure drop which must not be recognized as
a degree of filter contamination.
Max. basic
pressure 300mbar
The basic pressure ascertained must be lower than the max. basic
pressure, otherwise an error will be shown in the display.