Explosion protection
5.1 ATEX
SITRANS SL
Operating Instructions, 12/2010, A5E01132948-04
69
Materials in the sensor pair
The sensor pair (transmitter and receiver) is built mainly using stainless or surface treated
steel and Aluminium 231 (maximum magnesium content 0.5%). The O-rings and gaskets
used are made of FKM (fluorine-polymer) or FFKM (perfluoro elastomer). The process
interface consists of a borosilicate glass window and an O-ring made of FKM. If the gas
purging of the sensor will fail the O-rings will be the limiting component for the temperature.
They can withstand 215 °C/420 °F (FKM).
Pressure Safety
In some applications the process can be over pressurized. Normally this is not a situation
where the measurements will be adequate.
WARNING
The high pressure glass in the sensors must not be subject to any mechanical impact which
might cause damage to the glass (scratch, gash etc.). Only use a soft cloth for cleaning of
the glass. Make sure that it is safe to dismount the sensor before cleaning.
WARNING
Make sure all plugs and tube fittings are sealed with the enclosed pipe thread Sealant
(Swagelok MS-PTS-6). (Instructions given on the sealant tube must be carefully followed).
Approval
The concept of the ATEX approval is that the system is not modified and that special ATEX
approved cables and bushings are used. An absolute condition for the approval is that the
equipment is setup according to ATEX system set-up (Page 71) .
Liability
Following commissioning, the total responsibility is with the owner.