FISCHER DE49 A Series, Operating Manual

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FISCHER Mess- und Regeltechnik GmbH Assembly | 3
BA_EN_DE49_A 11/36
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H (high) L (low)
Fig. 4: Process connection
The pressure lines must be installed at an inclination so that when fluids are
measured no air pockets are created or when measuring gases, no water pock-
ets are created. If the required inclination is not reached, water or air filters must
be installed at suitable places.
The pressure lines must be kept as short as possible and installed without any
tight bends to avoid delays.
If the pressure sensing lines are already pressurised at the time of commission-
ing, zero-point control and adjustment cannot be performed. In such cases, the
device should be only connected to the mains without the pressure sensing
lines.
The device has several connection options for the process connection. There
must be appropriate hoses and pipes available on the system side.
The process connections are marked with (H) and (L) symbols on the device.
The pressure lines must be mounted according to these symbols.
1. Differential pressure measurement
Higher pressure
lower pressure
2. Pressure measurement
Pressure
open
3. Under-pressure measurement
open
Under-pressure
3.3 Electrical connections
Fig. 5: Ground connection
The electrical connection may only be realised by authorised and qualified spe-
cialists that have undergone additional training or briefings or have a permit to
work on explosion-protected units in potentially explosive systems.
Risks emanating from electrical current of voltage should be prevented by
means of suitable action.
• When connecting the unit, the national and international electro-technical
regulations must be observed.
• Disconnect the system from the mains, before electrically connecting the
device.
• Do not connect the connector if strained.
• A CE-conform mains adapter with a slow 200 mA fuse only may be used in
the power supply circuit.
• To ensure safe operation of the device, the power circuit must satisfy the ig-
nition protection category "Intrinsic safety" category "ia" (see Technical
data).
WARNING
Static electricity
The housing is made of a conductive plastic. To discharge any static charging,
the housing must be grounded
The ground terminal is suitable for connecting fine-wire conductors up to 4 mm
2
or single-wire conductors up to 6 mm
2
.