Idiomas disponibles
Idiomas disponibles
3.3
Intended use
Air Guard is a large-scale permanent installation which
continuously monitors the limit values for specific
contaminations in the connected breathing air supply using the
installed sensors.
Air Guard analyses the measured values and triggers an alarm
when limit values are exceeded. This alarm activates 2
potential-free contacts in the device which, for example, can be
used to shut down a compressor and simultaneously lock the
taps.
The alarms are also transmitted by the lamps installed on the
front of the device or by an external visual warning (optional).
3.4
Limitations on intended use
Any use other than that mentioned in the "Intended use"
chapter shall be regarded as improper usage. The following in
particular is not permitted:
Measuring gases other than those specified
Measurement of air, which does not correspond to
DIN EN 12021 and which has a dew point higher than -
20 °C. This means that the compliant condition must
immediately be restored if the limit value is exceeded.
Use of the Air Guard in a depressurised state without the
"Intelligent purging" setting.
4
Operation
CAUTION
To prevent unauthorised access, Dräger Air Guard must be
kept locked at all times. Make sure the key is stored in a safe
place that can only be accessed by authorised technical
personnel.
NOTE
If the signal lamp does not light up green, one or more
measurements have measured values above the preset alarm
value and/or warning value, or there is a malfunction present.
The operating organisation must define whether and which
further steps must be taken by the user.
A measured value between the alarm and the warning values
indicates that the concentration is approaching the alarm value
and measures must be taken if necessary. The concentration
of the measured warning value is still below the limit value
according to the DIN EN 12021 standard.
NOTE
Air Guard may only be commissioned by Dräger Service or
authorised technical personnel.
4.1
Installation
CAUTION
Danger due to contaminated air
There is a delay before contamination is detected, the alarm is
triggered and the potential-free contacts are activated; this
delay is set depending on the ratio between the volume of the
gas flow system and the Air Guard or the filling station and the
duration of the actual measurement.
This is primarily due to the fact that the volume flow within the
Air Guard has to be greatly reduced for correct measurement,
while the volume flow to the pressure vessels occurs without a
delay depending on the system. Take this into consideration
when calculating the length of the lines and installing them.
A T-piece (supplied) must be installed to connect the HP
version of the Air Guard to the pipeline network. To achieve the
shortest possible response time, the compressed air must first
be fed via the T-piece and then on to the consumers such as
the filling panel.
Owing to the lower pressure, different pipeline volumes do not
work so effectively with the LP version. For the pipes, a stub
with a small volume must be used.
The responsible service branch will provide support for the
design.
► A buffer must be included when the breathing air lines are
planned. The stub to the Air Guard must exit upstream of
the buffer. The taps must be downstream of the buffer.
Direct extraction of the supplied air is not permitted.
► In case of doubt, contact Dräger.
NOTE
It is recommended that a non-return valve be installed in the
compressed gas line upstream of the connectors for the
pressure vessels to be filled.
► This prevents air from exiting the pressure vessels via the
Air Guard, avoiding pressure losses.
NOTE
The Air Guard may only be used in enclosed spaces and must
be installed in such a way that the visual warning can be seen
by users, or a readily visible external warning lamp must be
installed.
1. Mount the Air Guard on the wall in a good location using
four suitable fasteners. Take the weight of the device into
account (see chapter 9). Mount the Air Guard so that
a. The underside (connection line) is horizontal and
b. The touchscreen is easy to access.
4.2
Preparations for use
NOTE
When the breathing air supply is turned on, an increased CO
concentration may occur. This happens especially after the
compressor has been idle for a longer period of time. In this
case, activate the purge to restore the Air Guard to its
operating condition.
4.2.1
High-pressure breathing connection (HP)
CAUTION
The maximum input pressure of 330 bar is not permitted to be
exceeded in the high-pressure version of the Air Guard
because the Air Guard can be damaged by higher pressures.
1. Use a T-piece to connect the Air Guard to the local system.
In order for the T-piece to be turned more easily for final
assembly, it is preassembled only hand-tight. After
assembly, the T-piece must be tightened.
2. Pressurise the pipeline system.
Operation
en
2
21
