GB-2
D
GB
F
NL
I
E
Checking the usage
DG
To monitor rising and falling pressure.
Positive
pressure
Negative pres-
sure
Differential
pressure
DG..S
NH
3
, O
2
,
air
–
–
This function is only guaranteed when used within
the specified limits – see page 4 (Technical data).
Any other use is considered as non-compliant.
Type code
Code
Description
DG
Gas pressure switch
6 – 500
Max. setting in mbar
S
Positive pressure (NH
3
, O
2
)
G
With gold-plated contacts
-3
-4
-5
-6
-9
Electrical connection
via screw terminals
via screw terminals, IP 65
4-pin plug, without socket
4-pin plug, with socket
4-pin plug, with socket, IP 65
K2
T
T2
N
Red/green pilot LED for 24 V DC/AC
Blue pilot lamp for 230 V AC
Red/green pilot LED for 230 V AC
Blue pilot lamp for 120 V AC
A
External adjustment
Part designations
1
2
3
4
1
Upper housing section with cover
2
Lower housing section
3
Hand wheel
4
M16 cable gland
Type label
Max. inlet pressure, mains voltage, ambient tem-
perature, enclosure: see type label.
DG
2
1
3
D-49018 Osnabrück, Germany
Installation
CAUTION
Please observe the following to ensure that the DG
is not damaged during installation and operation:
– As the temperature increases, the diffusion rate
of NH
3
through the diaphragm also increases
which can cause corrosion of the contacts. For
this reason, query the closed contacts for opening.
– The medium NH
3
must not condense as this can
lead to increased corrosion of the lower section
(pressure supply can become blocked) and de-
formation of the diaphragm (causing the switching
point to shift).
– Continuous operation at high temperatures accel-
erates the ageing of elastomer materials. In places
where a high thermal capacity is required, thermal
equipment trips must be installed upstream of
the DG.
– Use approved sealing material only.
–
Check max. ambient temperature – see
– Condensation or vapours containing silicone must
not be allowed to get into the housing. At subzero
temperatures malfunctions/failures due to icing
can occur.
– The service life will be shorter if subject to ozone
concentrations exceeding 200 μg/m
3
. When in-
stalling outdoors, place the DG in a roofed area
and protect from direct sunlight (even IP 65 ver-
sion). To avoid condensation, the cover with pres-
sure equalization element can be used.
– Avoid subjecting the DG to strong or violent vibra-
tions.
▷
Installation position as required, preferably with
vertical diaphragm. Then the switching point p
S
corresponds to the scale value SK set on the
hand wheel. In other installation positions, the
switching point p
S
will change and no longer
correspond to the scale value SK set on the
hand wheel. Check the switching point.
ps = SK
ps = SK + 0,18 mbar
ps = SK - 0,18 mbar
▷
The DG must not be in contact with masonry.
Minimum clearance 20 mm.
▷
Ensure that there is sufficient installation space.
▷
Ensure unobstructed view of the hand wheel.
1
Disconnect the system from the electrical power
supply.
2
Shut off the medium supply.
3
Ensure that the pipeline is clean.
