SS 20.600 Ex
– Supplementary instructions for use in explosive atmospheres ATEX Page 6
4 Application range
The ATEX version of the
SCHMIDT
®
Flow Sensor SS 20.600 Ex
(cate-
gory 3) is designed for stationary measurement of the flow velocity as well
as the air and gas temperature in potentially explosive atmospheres with
the following types of protection for:
Gases (Zone 2) :
II 3G Ex nA ic IIC T4 Gc
Special condition for use ("X"):
o The internal intrinsically safe circuit is isolated
1
from the
housing up to 30 V.
o A power supply according to protection class III is required
(SELV or PELV).
The permissible operating temperatures are:
o Electronics :
-20 ... +70 °C
o Sensor probe :
-40 ... +120 °C
Electrical datas:
o Rated voltage :
24 V
DC
± 20 %
o Rated current:
≤ 250 mA
o Measurement outputs:
0
… 10 V / 4 … 20 mA
o Impulse output:
f
=
0 … 100 Hz
U
max
= 28,8 V
DC
I
max
= 100 mA
o Relais output:
f
=
0 … 100 Hz
U
max
= 30 V
DC
I
max
= 50 mA
Enclosure:
o Degree of protecion:
IP65 (main enclosure), IP67 (sensor probe)
More technical data are given in the general "Instructions for Use
SS 20.600" (material no.: 535084.02).
1
ESD protection via in-house varistor installed between GND and housing.
