Correct purpose of use
Application area
Beck GmbH
Druckkontrolltechnik
Ferdinand-Steinbeis-Straße 4
71144 Steinenbronn
Operating instructions – Pressure Switch – Model - 901...EX
Rev.10
Page 5 of 18
2 Correct purpose of use
2.1 Application area
Purpose of use
The adjustable pressure switches have the following main purpose
Factory-set pressure switch monitoring overpressure, vacuum or differential pres-
sure of liquid and gaseous – also aggressive – media
Pressure setting and switching differential are factory-set by the Manufacturer
The pressure switch 901 Prescal© uses a scaled adjustment knob to enable the ad-
justment of trip and reset pressure without the use of a screwdriver.
The media that are being monitored occur in the following different phases
Gaseous (main application)
Potentially explosive gasses and dust (natural gas, bio-gas, solvents etc.)
Liquid
Flammable liquids (petrol, solvent etc.)
Use in zones in potentially explosive areas
Pressure switches are used to monitor the pressure difference in
areas of closed systems where there is a risk of gas explosion.
The device may be used in areas where there is a risk of gas or dust explosion
Two separate zonal areas can be connected via pressure connections P1 and P2 (are-
as 1 and 2)
Zone 1,2 or zone 21,22 may apply to the pressure connections (areas 1 and 2)
The surroundings (area 3) can be zone 1,2 or zone 21,22
2.2 CE conformity
The product complies with the following European directives:
Explosion protection directive
RoHS directive
Other information and verification can be found in the
Conformity declaration (see Chapter 9.3)
Area-1
Surrounding
Area-2
Equipment category
Equipment Protection
Level
Zone 0
Zone 1,2
1/2 G
Ga/Gb
Zone 21,22
Zone 21,22
2D
Db
Zone 1,2
Zone 1,2
2G
Gb
Zone 21,22
Zone 21,22
2D
Db
Surroun-
ding
Area-1
Area -2