Limitations Of The Intended Use; Operation; Installation; Preparations For Use - Dräger Air Guard Serie Instrucciones De Uso

en

Operation

3.4

Limitations of the 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

EN 12021 and whose dew point is higher than -20 °C. This
means that the compliant condition must immediately be
restored if the limit value is exceeded.
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.
NOTICE
If the signal lamp is not green, this means that one or more of
the pre-set alarm values was exceeded or there is a device
malfunction and the operator must define whether measures
need to be taken by the user, and if so, which measures.
NOTICE
Air Guard may only be commissioned by DrägerService or
authorised technical personnel.
4.1

Installation

CAUTION
Danger due to contaminated air
There is a delay before contamination is detected, the alarm
triggered and the potential-free contacts activated which is set
depending on the ratio between the volume of the gas line 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 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.
► If an alarm is triggered, indicating a contamination, the
following must be observed:
The measuring system has a measurement delay /

response time of at least 6 minutes because of the
duration of the measurement.
The measurement delay must also be taken into

account if there is a shutoff valve upstream of the
Air Guard. If the shutoff valve is shut too early,
contaminated air may be supplied but not detected by
the Air Guard because of the measurement delay.
The operator shall determine when to inspect, empty

and clean previously filled containers. Purge the
Air Guard (see chapter 4.4.5). Observe the
instructions for use for the sensors.
► In case of doubt, contact Dräger.
18
NOTICE
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.
NOTICE
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.
► To enable direct measurement, install the Air Guard close
to the device which generates the compressed air to
shorten the distance that gas needs to travel to reach the
Air Guard.
1. Mount the Air Guard on the wall in a good location using
four suitable fasteners. Keep in mind the weight of the
device (see chapter 9). Mount the Air Guard so that:
a. The underside (connection line) is horizontal and
b. The touchscreen is easy to access.
The manufacturer must be consulted before the device is
mounted. The measurement delay increases depending on
the length of the line.
4.2

Preparations for use

NOTICE
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 300 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.
Preassemble the T-piece hand-tight only, so that it can be
turned more easily for final assembly. After assembly, the
T-piece must be tightened.
2. Pressurise the pipeline system.
4.2.2

Medium pressure breathing connection (LP)

CAUTION
The maximum input pressure of 10 bar is not permitted to be
exceeded in the medium-pressure version of the Air Guard
because the Air Guard can be damaged by higher pressures.
1. Use a CEJN connection (346 series) to connect the
Air Guard to the local system.
2. Pressurise the pipeline system.
4.2.3

Connection of the potential-free contacts

The Air Guard has two potential-free contacts. These contacts
can turn off a breathing air compressor, for example. The
contacts are located on the internal terminal strip (X2 terminals
23 and 24 as well as X2 terminals 26 and 27) and are closed
2