Schmidt SS 20.600 - Special Gases and Parylene Versions; Mechanical Sensor Designs

Instructions for Use – SCHMIDT
®
Flow Sensor SS 20.600 Page 6
Version Special gases
The “Special gas” version of the SS 20.600 is equipped with a correction
for the measurement of certain gases and gas mixtures.
The sensor is adjusted and calibrated in air. Then a special correction for
the medium to be measured is applied to the sensor. Those corrections
have been determined for many gases in real gas ducts.
For gas mixtures, the correction is calculated according to the set volumic
mixing ratio.
The customer is responsible for the observance of all relevant
statutory provisions, standards and directives relating to the use
of gases.
Version Parylene
This option has an increased media resistance.
The corresponding adjustments comprise:
- The entire sensor head (including
its flow guiding chamber) is made of
stainless steel (1.4571).
- Only the sensor head is coated with
Parylene (see Figure 2-1).
The coating covers the entire sen-
sor head, including the sensor chip
within the flow chamer, up to just
before the assembly gap that results from the press fitting of the head
into the probe‘s tube.
- The fitting zone inside the tube is sealed by two O-rings made of media-
resistant FKM.
The specific suitability for the application is to be checked by the customer
himself.
Mechanical versions
The sensor SS 20.600 is available in the following basic designs:
 Compact sensor:
The sensor probe is mechanically fixed at the main enclosure.
 Remote sensor:
The sensor probe is connected to the main enclosure via an electrical
cable.
The designs and their dimensions can be obtained from the dimensional
drawings in chapter 9.
For ordering options (probe and cable lengths) see table 9 or the product
brochure.
Figure 2-1
34